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                                                                    EXHIBIT 10.2


                              AMENDED AND RESTATED
                             STOCK OPTION AGREEMENT

     Amended and Restated Stock Option Agreement, dated as of June 11, 2001 and
amended and restated on July 25, 2001 (as of June 11, 2001), between Banknorth
Group, Inc., a Maine corporation ("Grantee"), and MetroWest Bank, a
Massachusetts-chartered savings bank ("Issuer").

                              W I T N E S S E T H:

     WHEREAS, Grantee and Issuer have entered into an Amended and Restated
Agreement and Plan of Reorganization of even date herewith (the "Reorganization
Agreement"), pursuant to which the Company will be combined with an existing
national bank subsidiary of Parent in a series of transactions and in connection
therewith each outstanding share of Company Common Stock (except Dissenting
Shares and Treasury Stock) shall be converted into the right to receive the
Consolidation Consideration; and

     WHEREAS, as a condition and an inducement to Grantee to enter into the
Reorganization Agreement, Issuer has agreed to grant Grantee the Option (as
hereinafter defined);

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants
and agreements set forth herein and in the Reorganization Agreement, the parties
hereto agree as follows:

     1.   (a)  Issuer hereby grants to Grantee an unconditional, irrevocable
option (the "Option") to purchase, subject to the terms hereof, up to an
aggregate of 2,851,756 fully paid and nonassessable shares (the "Option Shares")
of common stock, par value $0.10 per share, of Issuer (the "Common Stock") at a
price per share equal to $8.76 (the "Option Price"); provided, however, that in
no event shall the number of shares for which this Option is exercisable exceed
19.9% of the issued and outstanding shares of Common Stock. The number of shares
of Common Stock that may be received upon the exercise of the Option and the
Option Price are subject to adjustment as herein set forth.

          (b)  In the event that any additional shares of Common Stock are
either (i) issued or otherwise become outstanding after the date of this
Agreement (other than pursuant to this Agreement and other than pursuant to an
event described in Section 5 hereof), including, without limitation, pursuant to
stock option or other employee plans or as a result of the exercise of
conversion rights, or (ii) redeemed, repurchased, retired or otherwise cease to
be outstanding after the date of this Agreement, the number of shares of Common
Stock subject to the Option shall be increased or decreased, as appropriate, so
that, after such event, such number equals 19.9% of the number of shares of
Common Stock then issued and outstanding without giving effect to any shares
subject to or issued pursuant to the Option. Nothing contained in this Section
l(b) or elsewhere in

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this Agreement shall be deemed to authorize Issuer or Grantee to breach any
provision of the Reorganization Agreement.

     2.   (a)  The Holder (as hereinafter defined) may exercise the Option, in
whole or part, and from time to time, if, but only if, both an Initial
Triggering Event (as hereinafter defined) and a Subsequent Triggering Event (as
hereinafter defined) shall have occurred prior to the occurrence of an Exercise
Termination Event (as hereinafter defined), provided that the Holder shall have
sent the Exercise Notice (as hereinafter defined) within ninety (90) days
following such Subsequent Triggering Event (or such later period as provided in
Section 10). Each of the following shall be an Exercise Termination Event: (i)
the Effective Time (as defined in the Reorganization Agreement); (ii)
termination of the Reorganization Agreement in accordance with the provisions
thereof if such termination occurs prior to the occurrence of an Initial
Triggering Event, except a termination by Grantee pursuant to Section 8.01(b) of
the Reorganization Agreement (unless the breach by Issuer giving rise to such
right of termination was non-volitional ( a "Listed Termination")); or (iii) the
passage of 12 months (or such longer period as provided in Section 10) after
termination of the Reorganization Agreement if such termination follows the
occurrence of an Initial Triggering Event or is a Listed Termination, provided
that if an Initial Triggering Event continues or occurs beyond such termination
and prior to the passage of such 12-month-period, the Exercise Termination Event
shall be 12 months from the expiration of the Last Triggering Event but in no
event more than 18 months after such termination. The term "Last Triggering
Event" shall mean the last Initial Triggering Event to be in effect, and the
term "Holder" shall mean the permitted holder or holders of the Option pursuant
to this Agreement. Notwithstanding anything to the contrary contained herein,
the Option may not be exercised at any time when Grantee shall be in willful
material breach of any of its covenants or agreements contained in the
Reorganization Agreement such that Issuer shall be entitled to terminate the
Reorganization Agreement pursuant to Section 8.01(b) thereof as a result of such
a willful material breach.

          (b)  The term "Initial Triggering Event" shall mean any of the
following events or transactions occurring on or after the date hereof:

               (i)  Issuer or any Subsidiary (as hereinafter defined) of Issuer
          (an "Issuer Subsidiary"), without having received Grantee's prior
          written consent, shall have entered into an agreement to engage in an
          Acquisition Transaction (as hereinafter defined) with any person (the
          term "person" for purposes of this Agreement having the meaning
          assigned thereto in Sections 3(a)(9) and 13(d)(3) of the Securities
          Exchange Act of 1934, as amended (the "1934 Act"), and the rules and
          regulations thereunder), other than Grantee or any Subsidiary of
          Grantee (a "Grantee Subsidiary") or the Board of Directors of Issuer
          (the "Issuer Board") shall have recommended that the stockholders of
          Issuer approve or accept any Acquisition Transaction with any person
          other than Grantee or a Grantee Subsidiary. For purposes of this
          Agreement, (a) "Acquisition Transaction" shall mean (w) a merger or
          consolidation, or any similar transaction, involving Issuer or any
          Issuer Subsidiary, (x) a purchase, lease or other acquisition or
          assumption of all or any substantial part of the consolidated assets
          or consolidated deposits of Issuer or any



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          Issuer Subsidiary, (y) a purchase or other acquisition (including by
          way of merger, consolidation, share exchange or otherwise) of
          securities representing 10% or more of the voting power of Issuer or
          any Issuer Subsidiary or (z) any substantially similar transaction,
          provided that in no event shall (i) any merger, consolidation,
          purchase or similar transaction involving only Issuer and one or more
          of its Subsidiaries, or involving only any two or more of such
          Subsidiaries, be deemed to be an Acquisition Transaction, provided
          that any such transaction is not entered into in violation of the
          terms of the Reorganization Agreement, or (ii) the transactions
          contemplated by the Reorganization Agreement or the entering into of
          the Reorganization Agreement be deemed to be an Acquisition
          Transaction; and (b) "Subsidiary" shall have the meaning set forth in
          Rule 12b-2 under the 1934 Act;

               (ii)  After the date hereof, any person, other than Grantee or a
          Grantee Subsidiary, shall have acquired beneficial ownership or the
          right to acquire beneficial ownership of 10% or more of the
          outstanding shares of Common Stock (the term "beneficial ownership"
          for purposes of this Agreement having the meaning assigned thereto in
          Section 13(d) of the 1934 Act, and the rules and regulations
          thereunder);

               (iii) The stockholders of Issuer shall have voted and failed to
          approve the Reorganization Agreement at a meeting which has been held
          for that purpose or any adjournment or postponement thereof, or such
          meeting shall not have been held in violation of the Reorganization
          Agreement or shall have been cancelled prior to termination of the
          Reorganization Agreement if, in each case prior to such meeting (or if
          such meeting shall not have been held or shall have been cancelled,
          prior to such termination), it shall have been publicly announced that
          any person (other than Grantee or a Grantee Subsidiary) shall have
          made, or publicly disclosed an intention to make, a proposal to engage
          in an Acquisition Transaction;

               (iv) The Issuer Board, without having received Grantee's prior
          written consent, shall have withdrawn or modified, or publicly
          announced its intention to withdraw or modify in any manner adverse in
          any respect to Grantee, its recommendation that the stockholders of
          Issuer approve the transactions contemplated by the Reorganization
          Agreement in anticipation of engaging in an Acquisition Transaction,
          or Issuer or any Issuer Subsidiary shall have authorized, recommended
          or proposed, or publicly announced its intention to authorize,
          recommend or propose, an agreement to engage in an Acquisition
          Transaction with any person other than Grantee or a Grantee
          Subsidiary;

               (v)  Any person other than Grantee or a Grantee Subsidiary shall
          have filed with the Securities and Exchange Commission ("SEC") a
          registration statement or tender offer materials with respect to a
          potential exchange offer or tender offer that would constitute an
          Acquisition Transaction (or filed a preliminary proxy statement



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          with the SEC with respect to a potential vote by its stockholders to
          approve the issuance of shares to be offered in such an exchange
          offer);

               (vi)  Issuer shall have breached any covenant or obligation
          contained in the Reorganization Agreement after a proposal is made by
          any third party, other than Grantee or a Grantee Subsidiary, to engage
          in an Acquisition Transaction and following such breach (x) Grantee
          would be entitled to terminate the Reorganization Agreement (whether
          immediately or after the giving of notice or passage of time or both)
          and (y) such breach shall not have been cured prior to the Notice Date
          (as defined below); or

               (vii) Any person other than Grantee or a Grantee Subsidiary,
          without Grantee's prior written consent, shall have filed an
          application or notice with the Board of Governors of the Federal
          Reserve System (the "Federal Reserve Board") or other federal or state
          bank regulatory or antitrust authority, which application or notice
          has been accepted for processing, for approval to engage in an
          Acquisition Transaction.

          (c)  The term "Subsequent Triggering Event" shall mean any of the
following events or transactions occurring after the date hereof:

               (i)   The acquisition by any person (other than Grantee or any
          Grantee Subsidiary) of beneficial ownership of 25% or more of the then
          outstanding Common Stock; or

               (ii)  The occurrence of the Initial Triggering Event described in
          clause (i) of subsection (b) of this Section 2, except that the
          percentage referred to in clause (y) of the second sentence thereof
          shall be 25%.

          (d)  Issuer shall notify Grantee promptly in writing of the occurrence
of any Initial Triggering Event or Subsequent Triggering Event (together, a
"Triggering Event") of which it has notice, it being understood that the giving
of such notice by Issuer shall not be a condition to the right of the Holder to
exercise the Option.

          (e)  In the event the Holder is entitled to and wishes to exercise the
Option (or any portion thereof), it shall send to Issuer a written notice (an
"Exercise Notice," the date of which being herein referred to as the "Notice
Date") specifying (i) the total number of shares of Common Stock it will
purchase pursuant to such exercise and (ii) a place and date not earlier than
three business days nor later than 60 business days from the Notice Date for the
closing of such purchase (the "Closing," the date of which being herein referred
to as the "Closing Date"); provided that if prior notification to or approval of
the Federal Reserve Board or any other regulatory or antitrust agency is
required in connection with such purchase, the Holder shall promptly file the
required notice or application for approval, shall promptly notify Issuer of
such filing and shall expeditiously process the same and the



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period of time that otherwise would run pursuant to this sentence shall run
instead from the date on which any required notification periods have expired or
been terminated or such approvals have been obtained and any requisite waiting
period or periods shall have passed. Any exercise of the Option shall be deemed
to occur on the Notice Date relating thereto. The term "business day" for
purposes of this Agreement means any day, excluding Saturdays, Sundays and any
other day that is a legal holiday in the Commonwealth of Massachusetts or a day
on which banking institutions in the Commonwealth of Massachusetts are
authorized by law or executive order to close.

          (f)  At a Closing, the Holder shall (i) pay to Issuer the aggregate
purchase price for the Option Shares purchased pursuant to the exercise of the
Option in immediately available funds by wire transfer to a bank account
designated by Issuer and (ii) present and surrender this Agreement to Issuer at
its principal executive offices, provided that the failure or refusal of the
Issuer to designate such a bank account or accept surrender of this Agreement
shall not preclude the Holder from exercising the Option.

          (g)  At a Closing, simultaneously with the delivery of immediately
available funds as provided in subsection (f) of this Section 2, Issuer shall
deliver to the Holder a certificate or certificates representing the number of
Option Shares purchased by the Holder and, if the Option should be exercised in
part only, a new Option evidencing the rights of the Holder thereof to purchase
the balance of the Option Shares purchasable hereunder, and the Holder shall
deliver to Issuer a copy of this Agreement and a letter agreeing that the Holder
will not offer to sell or otherwise dispose of such shares in violation of
applicable law or the provisions of this Agreement.

          (h)  Certificates for Option Shares delivered at a Closing hereunder
may be endorsed (in the sole discretion of Issuer) with a restrictive legend
that shall read substantially as follows:

          "The transfer of the shares represented by this certificate is subject
     to certain provisions of an agreement between the registered holder hereof
     and Issuer and to resale restrictions arising under the Securities Act of
     1933, as amended. A copy of such agreement is on file at the principal
     office of Issuer and will be provided to the holder hereof without charge
     upon receipt by Issuer of a written request therefor."

It is understood and agreed that: (i) the reference to the resale restrictions
of the Securities Act of 1933, as amended (the "1933 Act") in the above legend
shall be removed by delivery of substitute certificate(s) without such reference
if the Holder shall have delivered to Issuer a copy of a letter from the staff
of the SEC, or an opinion of counsel, in form and substance reasonably
satisfactory to Issuer, to the effect that such legend is not required for
purposes of the 1933 Act; (ii) the reference to the provisions of this Agreement
in the above legend shall be removed by delivery of substitute certificate(s)
without such reference if the shares have been sold or transferred in compliance
with the provisions of this Agreement and under circumstances that do not
require the retention of such reference in the opinion of counsel to the Holder,
which shall be set forth in a written opinion in form and substance reasonably
satisfactory to Issuer; and (iii) the legend shall be removed in its entirety if
the conditions in the preceding clauses (i) and (ii) are both satisfied. In
addition, such certificates shall bear any other legend as may be required by
law.



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          (i)  Upon the giving by the Holder to Issuer of the written notice of
exercise of the Option provided for under paragraph (e) of this Section 2, the
tender of the applicable purchase price in immediately available funds and the
tender of a copy of this Agreement to Issuer, the Holder shall be deemed,
subject to the receipt of any necessary regulatory approvals, to be the holder
of record of the shares of Common Stock issuable upon such exercise,
notwithstanding that the stock transfer books of Issuer shall then be closed or
that certificates representing such shares of Common Stock shall not then be
actually delivered to the Holder. Issuer shall pay all expenses, and any and all
United States federal, state and local taxes and other charges that may be
payable in connection with the preparation, issue and delivery of stock
certificates under this Section 2 in the name of the Holder or its assignee,
transferee or designee.

     3.   Issuer agrees: (i) that it shall at all times maintain, free from
preemptive rights, sufficient authorized but unissued or treasury shares of
Common Stock so that the Option may be exercised without additional
authorization of Common Stock after giving effect to all other options,
warrants, convertible securities and other rights to purchase Common Stock; (ii)
that it will not, by charter amendment or through reorganization, consolidation,
merger, dissolution or sale of assets, or by any other voluntary act, avoid or
seek to avoid the observance or performance of any of the covenants,
stipulations or conditions to be observed or performed hereunder by Issuer;
(iii) promptly to take all action as may from time to time be required
(including without limitation (x) complying with all applicable premerger
notification, reporting and waiting period requirements specified in 15 U.S.C.
Section 18a and regulations promulgated thereunder and (y) in the event, under
the Bank Holding Company Act of 1956, as amended (the "BHCA"), or the Change in
Bank Control Act of 1978, as amended, or any state or other federal banking law,
prior approval of or notice to the Federal Reserve Board or to any state or
other federal regulatory authority is necessary before the Option may be
exercised, cooperating fully with the Holder in connection with the preparation
of such applications or notices and providing such information to the Federal
Reserve Board or such state or other federal regulatory authority as they may
require) in order to permit the Holder to exercise the Option and Issuer duly
and effectively to issue shares of Common Stock pursuant hereto; and (iv)
promptly to take all action provided herein to protect the rights of the Holder
against dilution.

     4.   This Agreement and the Option granted hereby are exchangeable, without
expense, at the option of the Holder, upon presentation and surrender of this
Agreement at the principal office of Issuer, for other Agreements providing for
Options of different denominations entitling the holder thereof to purchase on
the same terms and subject to the same conditions as are set forth herein in the
aggregate the same number of shares of Common Stock purchasable hereunder. The
terms "Agreement" and "Option" as used herein include any Stock Option
Agreements and related Options for which this Agreement (and the Option granted
hereby) may be exchanged. Upon receipt by Issuer of evidence reasonably
satisfactory to it of the loss, theft, destruction or mutilation of this
Agreement, and (in the case of loss, theft or destruction) of reasonably
satisfactory indemnification, and upon surrender and cancellation of this
Agreement, if mutilated, Issuer will execute and deliver a new Agreement of like
tenor and date. Any such new Agreement executed and delivered shall constitute
an additional contractual obligation on the part of Issuer, subject to the
aforementioned



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indemnification, if applicable, whether or not the Agreement so lost, stolen,
destroyed or mutilated shall at any time be enforceable by anyone.

     5.   In addition to the adjustment in the number of shares of Common Stock
that are purchasable upon exercise of the Option pursuant to Section 1 of this
Agreement, the number of Option Shares purchasable upon the exercise of the
Option and the Option Price shall be subject to adjustment from time to time as
provided in this Section 5. In the event of any change in, or distributions in
respect of, the Common Stock by reason of stock dividend, stock split, split-up,
merger, recapitalization, stock combination, subdivision, conversion, exchange
of shares, distribution on or in respect of the Common Stock or similar
transaction, the type and number of Option Shares subject to the Option, and the
Option Price therefor, shall be adjusted appropriately, and proper provision
shall be made in the agreements governing such transaction, so that Grantee
shall receive upon exercise of the Option the number and class of Option Shares
or other securities or property that Grantee would have received in respect of
Option Shares if the Option had been exercised immediately prior to such event,
or the record date therefor, as applicable.

     6.   Upon the occurrence of a Subsequent Triggering Event that occurs prior
to an Exercise Termination Event, Issuer shall, at the request of Grantee
delivered within six (6) months (or such later period as provided in Section 10)
following such Subsequent Triggering Event (whether on its own behalf or on
behalf of any subsequent holder of this Option (or part thereof) or any of the
Option Shares issued pursuant hereto), promptly prepare, file and keep current,
with respect to the Option and the Option Shares, a registration statement under
the 1933 Act, to the extent applicable, and/or any applicable securities
offering rules of a federal or state banking authority, and qualify such Option
and Option Shares for resale or other disposition under applicable state
securities laws, in each case in accordance with any plan of disposition
requested by Grantee. Issuer will use all reasonable efforts to cause such
registration statement promptly to become effective and then to remain effective
for such period not in excess of 180 days from the day such registration
statement first becomes effective or such shorter time as may be reasonably
necessary to effect such sales or other dispositions. Grantee shall have the
right to demand two such registrations. Issuer shall bear the costs of such
registrations (including, but not limited to, Issuer's attorneys' fees, printing
costs and filing fees, except for underwriting discounts or commissions,
brokers' fees and the fees and disbursements of Grantee's counsel related
thereto). The foregoing notwithstanding, if, at the time of any request by
Grantee for registration of the Option or Option Shares as provided above,
Issuer is in registration with respect to an underwritten public offering by
Issuer of shares of Common Stock, and if in the good faith judgment of the
managing underwriter or managing underwriters, or, if none, the sole underwriter
or underwriters, of such offering, the inclusion of the Option and/or Option
Shares would interfere with the successful marketing of the shares of Common
Stock offered by Issuer, the number of shares represented by the Option and/or
the number of Option Shares otherwise to be covered in the registration
statement contemplated hereby may be reduced; provided, however, that after any
such required reduction the number of shares represented by the Option and/or
the number of Option Shares to be included in such offering for the account of
the Holder shall constitute at least 25% of the total number of shares to be
sold by the Holder and Issuer in the aggregate; and provided further, however,
that if such reduction occurs, then Issuer shall file a registration statement
for the balance as promptly as practicable thereafter as to which no reduction


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pursuant to this Section 6 shall be permitted or occur and Holder shall
thereafter be entitled to one additional registration and the twelve (12) month
period referred to in the first sentence of this section shall be increased to
twenty four (24) months. Each such Holder shall provide all information
reasonably requested by Issuer for inclusion in any such registration statement
to be filed hereunder. If requested by any such Holder in connection with such
registration, Issuer shall become a party to any underwriting agreement relating
to the sale of such shares, but only to the extent of obligating itself in
respect of representations, warranties, indemnities and other agreements
customarily included in such underwriting agreements for Issuer. Upon receiving
any request under this Section 6 from any Holder, Issuer agrees to send a copy
thereof to any other person known to Issuer to be entitled to registration
rights under this Section 6, in each case by promptly mailing the same, postage
prepaid, to the address of record of the persons entitled to receive such
copies. Notwithstanding anything to the contrary contained herein, in no event
shall the number of registrations that Issuer is obligated to effect be
increased by reason of the fact that there shall be more than one Holder as a
result of any assignment or division of this Agreement.

     7.   (a)  Immediately prior to the occurrence of a Repurchase Event (as
described below), (i) at the request of any Holder delivered prior to an
Exercise Termination Event (or such later period as provided in Section 10),
Issuer (or any successor thereto) shall repurchase the Option from the Holder at
a price (the "Option Repurchase Price") equal to the amount by which (A) the
Market/Offer Price (as defined below) exceeds (B) the Option Price, multiplied
by the number of shares for which the Option may then be exercised, and (ii) at
the request of the owner of Option Shares from time to time (the "Owner"),
delivered within 90 days following such occurrence (or such later period as
provided in Section 10), Issuer (or any successor thereto) shall repurchase such
number of the Option Shares from the Owner as the Owner shall designate at a
price (the "Option Share Repurchase Price") equal to the greater of (A) the
Market/Offer Price and (B) the average exercise price per share paid by the
Owner for the Option Shares so designated. The term "Market/Offer Price" shall
mean the highest of (i) the price per share of Common Stock at which a tender
offer or exchange offer therefor has been made, (ii) the price per share of
Common Stock to be paid by any person, other than Grantee or a Grantee
Subsidiary, pursuant to an agreement with Issuer of the kind described in
Section 2(b)(i), (iii) the highest closing price for shares of Common Stock
within the six-month period immediately preceding the date of such required
repurchase of the Option or Option Shares, as the case may be, or (iv) in the
event of a sale of all or any substantial part of Issuer's assets or deposits,
the sum of the price paid in such sale for such consolidated assets or
consolidated deposits and the current market value of the remaining assets of
Issuer as determined by a nationally-recognized investment banking firm selected
by a majority in interest of the Holders or the Owners, as the case may be, and
reasonably acceptable to Issuer, divided by the number of shares of Common Stock
of Issuer outstanding at the time of such sale. In determining the Market/Offer
Price, the value of consideration other than cash shall be determined by a
nationally-recognized investment banking firm selected by the Holder or Owner,
as the case may be, and reasonably acceptable to Issuer.

          (b)  Each Holder and Owner, as the case may be, may exercise its right
to require Issuer to repurchase the Option and any Option Shares pursuant to
this Section 7 by surrendering for such purpose to Issuer, at its principal
office, a copy of this Agreement or certificates for Option



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Shares, as applicable, accompanied by a written notice or notices stating that
such Holder or Owner, as the case may be, elects to require Issuer to repurchase
this Option and/or Option Shares in accordance with the provisions of this
Section 7. As promptly as practicable, and in any event within five business
days after the surrender of the Option and/or certificates representing Option
Shares and the receipt of such notice or notices relating thereto, Issuer shall
deliver or cause to be delivered to the Holder the Option Repurchase Price
and/or to the Owner the Option Share Repurchase Price therefor or the portion
thereof that Issuer is not then prohibited under applicable law and regulation
from so delivering.

          (c)  To the extent that Issuer is prohibited under applicable law or
regulation, or as a consequence of administrative policy, or as a result of a
written agreement or other binding obligation with a governmental or regulatory
body or agency, from repurchasing the Option and/or the Option Shares in full,
Issuer shall immediately so notify each Holder and/or each Owner and thereafter
deliver or cause to be delivered, from time to time, to such Holder and/or such
Owner, as appropriate, the portion of the Option Repurchase Price and the Option
Share Repurchase Price, respectively, that it is no longer prohibited from
delivering, within two business days after the date on which Issuer is no longer
so prohibited; provided, however, that if Issuer at any time after delivery of a
notice of repurchase pursuant to paragraph (b) of this Section 7 is prohibited
under applicable law or regulation, or as a consequence of administrative
policy, or as a result of a written agreement or other binding obligation with a
governmental or regulatory body or agency, from delivering to the Holder and/or
the Owner, as appropriate, the Option Repurchase Price and the Option Share
Repurchase Price, respectively, in part or in full (and Issuer hereby undertakes
to use all reasonable efforts to obtain all required regulatory and legal
approvals and to file any required notices as promptly as practicable in order
to accomplish such repurchase), such Holder or Owner may revoke its notice of
repurchase of the Option and/or the Option Shares either in whole or to the
extent of the prohibition, whereupon, in the latter case, Issuer shall promptly
(i) deliver to the Holder and/or the Owner, as appropriate, that portion of the
Option Repurchase Price and/or the Option Share Repurchase Price that Issuer is
not prohibited from delivering with respect to Options or Option Shares as to
which the Holder or the Owner, as the case may be, has not revoked its
repurchase demand; and (ii) deliver, as appropriate, either (A) to the Holder, a
new Agreement evidencing the right of the Holder to purchase that number of
shares of Common Stock obtained by multiplying the number of shares of Common
Stock for which the surrendered Agreement was exercisable at the time of
delivery of the notice of repurchase by a fraction, the numerator of which is
the Option Repurchase Price less the portion thereof theretofore delivered to
the Holder and the denominator of which is the Option Repurchase Price, and/or
(B) to such Owner, a certificate for the Option Shares it is then so prohibited
from repurchasing.

          (d)  For purposes of this Agreement, a "Repurchase Event" shall be
deemed to have occurred upon the occurrence of any of the following events or
transactions after the date hereof:

               (i)  the acquisition by any person (other than Grantee or any
     Grantee Subsidiary) of beneficial ownership of 50% or more of the then
     outstanding Common Stock; or



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               (ii)  the consummation of any Acquisition Transaction described
     in Section 2(b)(i) hereof, except that the percentage referred to in clause
     (y) of the second sentence thereof shall be 50%;

provided that no such event shall constitute a Repurchase Event unless a
Subsequent Triggering Event shall have occurred prior to an Exercise Termination
Event. The parties hereto agree that Issuer's obligations to repurchase the
Option or Option Shares under this Section 7 shall not terminate upon the
occurrence of any Exercise Termination Event unless no Subsequent Triggering
Event shall have occurred prior to the occurrence of an Exercise Termination
Event.

     8.   (a)  In the event that prior to an Exercise Termination Event, Issuer
shall enter into an agreement (i) to consolidate with or merge into any person,
other than Grantee or a Grantee Subsidiary, or engage in a plan of exchange with
any person, other than Grantee or a Grantee Subsidiary, and Issuer shall not be
the continuing or surviving corporation of such consolidation or merger or the
acquiror in such plan of exchange, (ii) to permit any person, other than Grantee
or a Grantee Subsidiary, to merge into Issuer or be acquired by Issuer in a plan
of exchange and Issuer shall be the continuing or surviving or acquiring
corporation, but, in connection with such merger or plan of exchange, the then
outstanding shares of Common Stock shall be changed into or exchanged for stock
or other securities of any other person or cash or any other property or the
then outstanding shares of Common Stock shall after such merger or plan of
exchange represent less than 50% of the outstanding shares and share equivalents
of the merged or acquiring company, or (iii) to sell or otherwise transfer all
or a substantial part of its or any Issuer Subsidiary's consolidated assets or
consolidated deposits to any person, other than Grantee or a Grantee Subsidiary,
then, and in each such case, the agreement governing such transaction shall make
proper provision so that the Option shall, upon the consummation of any such
transaction and upon the terms and conditions set forth herein, be converted
into, or exchanged for, an option (the "Substitute Option"), at the election of
any Holder, of either (x) the Acquiring Corporation (as hereinafter defined) or
(y) any person that controls the Acquiring Corporation.

          (b)  The following terms have the meanings indicated:

               (i)   "Acquiring Corporation" shall mean (i) the continuing or
     surviving person of a consolidation or merger with Issuer (if other than
     Issuer), (ii) the acquiring person in a plan of exchange in which Issuer is
     acquired, (iii) Issuer in a merger or plan of exchange in which Issuer is
     the continuing or surviving or acquiring person, and (iv) the transferee of
     all or a substantial part of Issuer's consolidated assets or consolidated
     deposits (or the assets or deposits of an Issuer Subsidiary).

               (ii)  "Substitute Common Stock" shall mean the common stock
     issued by the issuer of the Substitute Option upon exercise of the
     Substitute Option.

               (iii) "Assigned Value" shall mean the Market/Offer Price, as
     defined in Section 7.



                                       10
<PAGE>   11

               (iv) "Average Price" shall mean the average closing price of a
     share of the Substitute Common Stock for the one year immediately preceding
     the consolidation, merger, share exchange or sale in question, but in no
     event higher than the closing price of the shares of Substitute Common
     Stock on the day preceding such consolidation, merger, share exchange or
     sale; provided that if Issuer is the issuer of the Substitute Option, the
     Average Price shall be computed with respect to a share of common stock
     issued by the person merging into Issuer or by any company which controls
     or is controlled by such person, as the Holder may elect.

          (c)  The Substitute Option shall have the same terms as the Option,
provided that if the terms of the Substitute Option cannot, for legal reasons,
be the same as the Option, such terms shall, to the extent legally permissible,
be as similar as possible to, and in no event less advantageous to the Holder
than, the terms of the Option. The issuer of the Substitute Option also shall
enter into an agreement with the then Holder or Holders of the Substitute Option
in substantially the same form as this Agreement (after giving effect for such
purpose to the provisions of Section 9), which agreement shall be applicable to
the Substitute Option.

          (d)  The Substitute Option shall be exercisable for such number of
shares of Substitute Common Stock as is equal to the Assigned Value multiplied
by the number of shares of Common Stock for which the Option was exercisable
immediately prior to the event described in the first sentence of Section 8(a),
divided by the Average Price. The exercise price of the Substitute Option per
share of Substitute Common Stock shall then be equal to the Option Price
multiplied by a fraction, the numerator of which shall be the number of shares
of Common Stock for which the Option was exercisable immediately prior to the
event described in the first sentence of Section 8(a) and the denominator of
which shall be the number of shares of Substitute Common Stock for which the
Substitute Option is exercisable.

          (e)  In no event, pursuant to any of the foregoing paragraphs, shall
the Substitute Option be exercisable for more than 19.9% of the shares of
Substitute Common Stock outstanding prior to exercise of the Substitute Option.
In the event that the Substitute Option would be exercisable for more than 19.9%
of the shares of Substitute Common Stock outstanding prior to exercise but for
this paragraph (e), the issuer of the Substitute Option (the "Substitute Option
Issuer") shall make a cash payment to Holder equal to the excess of (i) the
value of the Substitute Option without giving effect to the limitation in this
paragraph (e) over (ii) the value of the Substitute Option after giving effect
to the limitation in this paragraph (e). This difference in value shall be
determined by a nationally-recognized investment banking firm selected by a
majority in interest of the Holders and reasonably acceptable to the Acquiring
Corporation.

          (f)  Issuer shall not enter into any transaction described in
paragraph (a) of this Section 8 unless the Acquiring Corporation and any person
that controls the Acquiring Corporation assume in writing all the obligations of
Issuer hereunder.



                                       11
<PAGE>   12

     9.   (a)  At the request of the holder of the Substitute Option (the
"Substitute Option Holder") delivered to the Substitute Option Issuer, the
Substitute Option Issuer shall repurchase the Substitute Option from the
Substitute Option Holder at a price (the "Substitute Option Repurchase Price")
equal to the amount by which (i) the Highest Closing Price (as hereinafter
defined) exceeds (ii) the exercise price of the Substitute Option, multiplied by
the number of shares of Substitute Common Stock for which the Substitute Option
may then be exercised, and at the request of each owner (the "Substitute Share
Owner") of shares of Substitute Common Stock (the "Substitute Shares"), the
Substitute Option Issuer shall repurchase the Substitute Shares at a price (the
"Substitute Share Repurchase Price") equal to the greater of (A) the Highest
Closing Price and (B) the average exercise price per share paid by the
Substitute Share Owner for the Substitute Shares so designated, multiplied by
the number of Substitute Shares so designated. The term "Highest Closing Price"
shall mean the highest closing price for shares of Substitute Common Stock
within the six-month period immediately preceding the date the Substitute Option
Holder gives notice of the required repurchase of the Substitute Option or the
Substitute Share Owner gives notice of the required repurchase of the Substitute
Shares, as applicable.

          (b)  Each Substitute Option Holder and Substitute Share Owner, as the
case may be, may exercise its respective right to require the Substitute Option
Issuer to repurchase the Substitute Option and the Substitute Shares pursuant to
this Section 9 by surrendering for such purpose to the Substitute Option Issuer,
at its principal office, the agreement for such Substitute Option (or, in the
absence of such an agreement, a copy of this Agreement) and/or certificates for
Substitute Shares accompanied by a written notice or notices stating that the
Substitute Option Holder or the Substitute Share Owner, as the case may be,
elects to require the Substitute Option Issuer to repurchase the Substitute
Option and/or the Substitute Shares in accordance with the provisions of this
Section 9. As promptly as practicable, and in any event within two business days
after the surrender of the Substitute Option and/or certificates representing
Substitute Shares and the receipt of such notice or notices relating thereto,
the Substitute Option Issuer shall deliver or cause to be delivered to the
Substitute Option Holder the Substitute Option Repurchase Price and/or to the
Substitute Share Owner the Substitute Share Repurchase Price therefor, or the
portion(s) thereof which the Substitute Option Issuer is not then prohibited
under applicable law and regulation from so delivering.

          (c)  To the extent that the Substitute Option Issuer is prohibited
under applicable law or regulation, or as a consequence of administrative
policy, or as a result of a written agreement or other binding obligation with a
governmental or regulatory body or agency, from repurchasing the Substitute
Option and/or the Substitute Shares in part or in full, the Substitute Option
Issuer following a request for repurchase pursuant to this Section 9 shall
immediately so notify the Substitute Option Holder and/or the Substitute Share
Owner and thereafter deliver or cause to be delivered, from time to time, to the
Substitute Option Holder and/or the Substitute Share Owner, as appropriate, the
portion of the Substitute Option Repurchase Price and/or the Substitute Share
Repurchase Price, respectively, which it is no longer prohibited from
delivering, within two business days after the date on which the Substitute
Option Issuer is no longer so prohibited; provided, however, that if the
Substitute Option Issuer is at any time after delivery of a notice of repurchase
pursuant to subsection (b) of this Section 9 prohibited under applicable law or
regulation, or as a



                                       12
<PAGE>   13

consequence of administrative policy, or as a result of a written agreement or
other binding obligation with a governmental or regulatory body or agency, from
delivering to the Substitute Option Holder and/or the Substitute Share Owner, as
appropriate, the Substitute Option Repurchase Price and the Substitute Share
Repurchase Price, respectively, in full (and the Substitute Option Issuer shall
use all reasonable efforts to obtain all required regulatory and legal approvals
as promptly as practicable in order to accomplish such repurchase), the
Substitute Option Holder and/or Substitute Share Owner may revoke its notice of
repurchase of the Substitute Option or the Substitute Shares either in whole or
to the extent of the prohibition, whereupon, in the latter case, the Substitute
Option Issuer shall promptly (i) deliver to the Substitute Option Holder or
Substitute Share Owner, as appropriate, that portion of the Substitute Option
Repurchase Price or the Substitute Share Repurchase Price that the Substitute
Option Issuer is not prohibited from delivering; and (ii) deliver, as
appropriate, either (A) to the Substitute Option Holder, a new Substitute Option
evidencing the right of the Substitute Option Holder to purchase that number of
shares of the Substitute Common Stock obtained by multiplying the number of
shares of the Substitute Common Stock for which the surrendered Substitute
Option was exercisable at the time of delivery of the notice of repurchase by a
fraction, the numerator of which is the Substitute Option Repurchase Price less
the portion thereof theretofore delivered to the Substitute Option Holder and
the denominator of which is the Substitute Option Repurchase Price, and/or (B)
to the Substitute Share Owner, a certificate for the Substitute Option Shares it
is then so prohibited from repurchasing.

     10.  The 90-day or six-month periods for exercise of certain rights under
Sections 2, 6, 7 and 9 shall be extended: (i) to the extent necessary to obtain
all regulatory approvals for the exercise of such rights (for so long as the
Holder, Owner, Substitute Option Holder or Substitute Share Owner, as the case
may be, is using its reasonable best efforts to obtain such regulatory
approvals), and for the expiration of all statutory waiting periods; (ii) during
the pendency of any order, injunction or judgment that prohibits or delays
exercise of such rights; and (iii) to the extent necessary to avoid liability
under Section 16(b) of the 1934 Act by reason of such exercise.

     11.  (a)  Issuer hereby represents and warrants to Grantee as follows:

               (i)  Issuer has full corporate power and authority to execute and
     deliver this Agreement and to consummate the transactions contemplated
     hereby. The execution and delivery of this Agreement and the consummation
     of the transactions contemplated hereby have been duly and validly
     authorized by the Issuer Board and no other corporate proceedings on the
     part of Issuer are necessary to authorize this Agreement or to consummate
     the transactions so contemplated. This Agreement has been duly and validly
     executed and delivered by Issuer.

               (ii) The execution and delivery of this Agreement, the
     consummation of the transactions contemplated hereby and compliance by
     Issuer with any of the provisions hereof will not (i) conflict with or
     result in a breach of any provision of its Charter or Bylaws or a default
     (or give rise to any right of termination, cancellation or acceleration)
     under any of the terms, conditions or provisions of any note, bond,
     debenture, mortgage, indenture, license, material agreement or other
     material instrument or obligation to which Issuer is a



                                       13
<PAGE>   14

     party, or by which it or any of its properties or assets may be bound, or
     (ii) violate any order, writ, injunction, decree, statute, rule or
     regulation applicable to Issuer or any of its properties or assets.

               (iii) Issuer has taken all necessary corporate action to
     authorize and reserve and to permit it to issue, and at all times from the
     date hereof through the termination of this Agreement in accordance with
     its terms will have reserved for issuance upon the exercise of the Option,
     that number of shares of Common Stock equal to the maximum number of shares
     of Common Stock at any time and from time to time issuable hereunder, and
     all such shares, upon issuance pursuant thereto, will be duly authorized,
     validly issued, fully paid and nonassessable, and will be delivered free
     and clear of all claims, liens, encumbrances and security interests and not
     subject to any preemptive rights.

          (b)  Grantee hereby represents and warrants to Issuer that:

               (i)   Grantee has full corporate power and authority to execute
     and deliver this Agreement and to perform its obligations hereunder. The
     execution and delivery of this Agreement by Grantee and the performance of
     its obligations hereunder by Grantee have been duly and validly authorized
     by all necessary corporate action on the part of Grantee and no other
     corporate proceedings on the part of Grantee are necessary to authorize
     this Agreement for Grantee to perform its obligations hereunder. This
     Agreement has been duly and validly executed and delivered by Grantee.

               (ii)  The Option is not being, and any shares of Common Stock or
     other securities acquired by Grantee upon exercise of the Option will not
     be, acquired with a view to the public distribution thereof and will not be
     transferred or otherwise disposed of except in a transaction registered or
     exempt from registration under the 1933 Act and any applicable securities
     offering rules of a federal or state banking authority.

     12.  Neither of the parties hereto may assign or otherwise transfer any of
its rights or obligations under this Agreement or the Option created hereunder
to any other person, without the express written consent of the other party,
except that in the event a Subsequent Triggering Event shall have occurred prior
to an Exercise Termination Event, Grantee, subject to the express provisions
hereof, may assign in whole or in part its rights and obligations hereunder,
provided, however, that until the date 15 days following the date on which the
Federal Reserve Board approves an application by Grantee under the BHCA to
acquire the shares of Common Stock subject to the Option, Grantee may not assign
its rights under the Option except in (i) a widely dispersed public
distribution, (ii) a private placement in which no one party acquires the right
to purchase in excess of 2% of the voting shares of Issuer, (iii) an assignment
to a single party (e.g., a broker or investment banker) for the sole purpose of
conducting a widely dispersed public distribution on Grantee's behalf or (iv)
any other manner approved by the Federal Reserve Board.

     13.  Each of Grantee and Issuer will use all reasonable efforts to make all
filings with, and to obtain consents of, all third parties and governmental
authorities necessary to the consummation



                                       14
<PAGE>   15

of the transactions contemplated by this Agreement, including, without
limitation, applying to the Federal Reserve Board under the BHCA for approval to
acquire the shares issuable hereunder and applying for listing or quotation of
such shares on any exchange or quotation system on which the Common Stock is
then listed or quoted.

     14.  (a)  Notwithstanding any other provision of this Agreement, in no
event shall the Grantee's Total Profit (as hereinafter defined) exceed
$10,000,000 (the "Maximum Profit") and, if it otherwise would exceed such
amount, the Grantee, at its sole election, shall either (i) reduce the number of
shares of Common Stock subject to this Option, (ii) deliver to the Issuer for
cancellation Option Shares previously purchased by Grantee, (iii) pay cash to
the Issuer or (iv) any combination thereof, so that Grantee's actually realized
Total Profit shall not exceed the Maximum Profit after taking into account the
foregoing actions. As used herein, the term "Total Profit" shall mean the
aggregate amount (before taxes) of the following: (i) the amount received by
Grantee pursuant to Issuer's repurchase of the Option (or any portion thereof)
pursuant to Section 7 hereof, (ii) (x) the amount received by Grantee pursuant
to Issuer's repurchase of the Option Shares pursuant to Section 7 hereof, less
(y) the Grantee's purchase price for such Option Shares, (iii) (x) the net cash
amounts received by Grantee pursuant to the sale of Option Shares (or any other
securities into which such Option Shares are converted or exchanged) to any
unaffiliated party, less (y) the Grantee's purchase price of such Option Shares,
(iv) any amounts received by Grantee on the transfer of the Option (or any
portion thereof) to any unaffiliated party and (v) any equivalent amount with
respect to the Substitute Option.

          (b)  Notwithstanding any other provision of this Agreement, this
Option may not be exercised for a number of shares as would, as of the date of
exercise, result in a Notional Total Profit (as hereinafter defined) of more
than the Maximum Profit, provided that nothing in this sentence shall restrict
any exercise of the Option permitted hereby on any subsequent date. As used
herein, the term "Notional Total Profit" with respect to any number of shares as
to which Grantee may propose to exercise this Option shall be the Total Profit
determined as of the date of such proposed exercise assuming that this Option
were exercised on such date for such number of shares and assuming that such
shares, together with all other Option Shares held by Grantee and its affiliates
as of such date, were sold for cash at the closing market price for the Common
Stock as of the close of business on the preceding trading day (less customary
brokerage commissions).

     15.  The parties hereto acknowledge that damages would be an inadequate
remedy for a breach of this Agreement by either party hereto and that the
obligations of the parties hereto shall be enforceable by either party hereto
through injunctive or other equitable relief. In connection therewith, both
parties waive the posting of any bond or similar requirement.

     16.  If any term, provision, covenant or restriction contained in this
Agreement is held by a court or a federal or state regulatory agency of
competent jurisdiction to be invalid, void or unenforceable, the remainder of
the terms, provisions and covenants and restrictions contained in this Agreement
shall remain in full force and effect, and shall in no way be affected, impaired
or invalidated. If for any reason such court or regulatory agency determines
that the Holder is not permitted to acquire, or Issuer or Substitute Option
Issuer, as the case may be, is not permitted to



                                       15
<PAGE>   16

repurchase pursuant to Section 7 or Section 9, as the case may be, the full
number of shares of Common Stock provided in Section l(a) hereof (as adjusted
pursuant to Section l(b) or Section 5 hereof), it is the express intention of
Issuer (which shall be binding on the Substitute Option Issuer) to allow the
Holder to acquire or to require Issuer or Substitute Option Issuer, as the case
may be, to repurchase such lesser number of shares as may be permissible,
without any amendment or modification hereof.

     17.  All notices, requests, claims, demands and other communications
hereunder shall be deemed to have been duly given when delivered in person, by
fax, telecopy or by registered or certified mail (postage prepaid, return
receipt requested) at the respective addresses of the parties set forth in the
Reorganization Agreement.

     18.  This Agreement shall be governed by and construed in accordance with
the laws of the State of Maine, without regard to the conflict of law principles
thereof.

     19.  This Agreement may be executed in two or more counterparts, each of
which shall be deemed to be an original, but all of which shall constitute one
and the same agreement.

     20.  Except as otherwise expressly provided herein, each of the parties
hereto shall bear and pay all costs and expenses incurred by it or on its behalf
in connection with the transactions contemplated hereunder, including fees and
expenses of its own financial consultants, investment bankers, accountants and
counsel.

     21.  Except as otherwise expressly provided herein or in the Reorganization
Agreement, this Agreement contains the entire agreement between the parties with
respect to the transactions contemplated hereunder and supersedes all prior
arrangements or understandings with respect thereof, written or oral, including
without limitation the Stock Option Agreement, dated as of June 11, 2001. The
terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the parties hereto and their respective successors and permitted
assigns. Nothing in this Agreement, express or implied, is intended to confer
upon any party, other than the parties hereto, and their respective successors
and permitted assigns any rights, remedies, obligations or liabilities under or
by reason of this Agreement, except as expressly provided herein.

     22.  Capitalized terms used in this Agreement and not defined herein shall
have the meanings assigned thereto in the Reorganization Agreement.




                                       16
<PAGE>   17

     IN WITNESS WHEREOF, each of the parties has caused this Agreement to be
executed on its behalf by its officers thereunto duly authorized, all as of the
date first above written.

                               METROWEST BANK



                               By:    /s/ John J. McArdle III
                                      -------------------------------------
                               Name:  John J. McArdle III
                               Title: Chief Executive Officer


                               BANKNORTH GROUP, INC.



                               By:    /s/ Peter J. Verrill
                                      -------------------------------------
                               Name:  Peter J. Verrill
                               Title: Executive Vice President, Chief Operating
                                        Officer and Chief Financial Officer





                                       17