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                                                                     EXHIBIT 4.8

                                 GREY WOLF, INC.

                      NON-QUALIFIED STOCK OPTION AGREEMENT

         THIS STOCK OPTION AGREEMENT (the "Agreement") is entered into this 15th
day of May 2001, by and between Grey Wolf, Inc., a Texas corporation (the
"Company") and Robert E. Rose, an individual (the "Optionee").

                                    RECITALS

         WHEREAS, Optionee currently serves as a non-employee director of the
Company;

         WHEREAS, the Company desires to grant to Optionee non-qualified options
to purchase shares of the Company's common stock for services rendered and to be
rendered as a member of the Company's board of directors;

         WHEREAS, the undersigned parties desire to formalize such agreement
regarding the grant of stock options to Optionee as provided herein.

         NOW, THEREFORE, in consideration of the premises, material covenants
and agreements contained herein, and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereby
agree as follows:

         1. GRANT OF OPTION. As of the date hereof (the "Grant Date"), the
Company hereby grants to Optionee a non-qualified stock option (the "Option") to
purchase a total of 75,000 shares (the "Shares") of the Company's common stock,
par value $0.10 per share (the "Common Stock"), at an exercise price of $6.37
per share, subject to the terms and conditions provided herein.

         2. EXERCISE PERIOD. The Option shall be exercisable by Optionee as to
thirty-three percent (33%) of the Option Shares one (1) year after the date of
this Agreement, as to an additional thirty-three percent (33%) of the Option
Shares two (2) years after the date of this Agreement and, as to an additional
thirty-four percent (34%) of the Option Shares three (3) years after the date of
this Agreement. The Option shall expire and terminate as to any Option Shares
not purchased by the Optionee on or before the tenth anniversary of the date of
this Agreement (the "Expiration Date"), subject to earlier termination as set
forth herein. Notwithstanding any other provision of this Agreement to the
contrary, the Option shall be immediately exercisable by Optionee as to one
hundred percent (100%) of the Option Shares as provided in Section 11(d) of this
Agreement.

         3. EXERCISE OF OPTION. This Option shall be exercisable during the
exercise period, subject to the provisions, as follows:

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                  (a) Right of Exercise. This Option is exercisable at any time
         during the exercise period, in whole or in part; provided, however,
         that this Option may only be exercisable to acquire whole shares of
         Common Stock.

                  (b) Method of Exercise. This Option is exercisable by delivery
         of this Agreement and a written notice to the attention of the
         Secretary of the Company, no fewer than five business days before the
         proposed effective date of exercise, signed by Optionee, specifying the
         number of Shares to be acquired on, and the effective date of, such
         exercise. Optionee may withdraw notice of exercise of this Option at
         any time before close of business on the business day preceding the
         proposed exercise date, and in this instance, the Company will return
         this Agreement to the Optionee.

                  (c) Method of Payment. Payment of the exercise price for the
         Shares purchased under this Option shall be delivered, in person or by
         certified mail to the attention of the Secretary of the Company, on the
         effective date of exercise either (i) in cash, or by certified check,
         bank cashier's check, payable to the order of the Company or by wire
         transfer to an account designated in writing by the Company to the
         Optionee, or (ii) subject to the approval of the board of directors of
         the Company, (A) in shares of Common Stock owned by the Optionee and
         valued at their fair market value on the effective date of exercise, as
         determined by such board in its sole discretion, (B) through a cashless
         exercise, in which the Optionee shall exchange a number of the options
         subject to such a cashless exercise for that number of shares of Common
         Stock determined by multiplying the number of shares into which such
         exchanged option is exercisable by a fraction, the numerator of which
         is the fair market value of a share of Common Stock on the exercise
         date, as determined by such board in its sole discretion, minus the
         exercise price for such option, and the denominator of which is such
         fair market value of a share of Common Stock on the exercise date, or
         (C) in any combination of the payment methods described in (i) or
         (ii)(A) or (B), above. If payment is made in shares of Common Stock
         such shares must be delivered to the Secretary, duly endorsed in blank
         or accompanied by stock powers duly executed in blank, and any other
         documents that the Secretary may require.

         4. RESTRICTIONS ON EXERCISE. This Option may not be exercised if the
issuance of such Shares or the method of payment of the consideration for such
Shares would constitute a violation of any applicable federal or state
securities or other laws or regulations, including any rule under Part 207 of
Title 12 of the Code of Federal Regulations ("Regulation G") as promulgated by
the Federal Reserve Board, or any rules or regulations of any stock exchange on
which the Common Stock may be listed.

         5. NON-TRANSFERABILITY OF OPTION. During the lifetime of the Optionee,
this Option may only be exercised by the Optionee. This Option is not assignable
or transferable, in whole or in part, other than by will or by the laws of
descent and distribution.

         6. ISSUANCE OF CERTIFICATE. As soon as reasonably practicable after the
exercise of this Option in accordance with Section 3, the Company shall issue to
the Optionee a certificate representing


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the Shares acquired, together with delivery of a new stock option agreement to
the extent any Options remain after such exercise. Each certificate representing
Shares shall bear conspicuous legends worded substantially as follows, in
addition to any other legends required by law:

THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED ("ACT"), OR UNDER ANY APPLICABLE STATE SECURITIES LAWS,
AND THEY CANNOT BE OFFERED FOR SALE, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE
HYPOTHECATED EXCEPT IN ACCORDANCE WITH THE REGISTRATION REQUIREMENTS OF THE ACT
AND SUCH STATE LAWS OR UPON DELIVERY TO THIS CORPORATION OF AN OPINION OF LEGAL
COUNSEL SATISFACTORY TO THE CORPORATION THAT AN EXEMPTION FROM REGISTRATION IS
AVAILABLE.

THE CORPORATION IS AUTHORIZED TO ISSUE SHARES OF MORE THAN ONE CLASS OF STOCK OR
MORE THAN ONE SERIES OF A CLASS. THE CORPORATION WILL FURNISH A STATEMENT OF THE
POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE, PARTICIPATING, OPTIONAL OR OTHER
SPECIAL RIGHTS OF EACH CLASS OR STOCK OR SERIES THEREOF AND THE QUALIFICATIONS,
LIMITATIONS OR RESTRICTIONS OF SUCH PREFERENCES AND/OR RIGHTS, WITHOUT CHARGE,
TO THE HOLDER OF THIS CERTIFICATE UPON RECEIPT BY THE CORPORATION AT ITS
PRINCIPAL PLACE OF BUSINESS OR REGISTERED OFFICE OF A WRITTEN REQUEST FROM THE
HOLDER REQUESTING SUCH COPY.

THE ARTICLES OF INCORPORATION OF THIS CORPORATION DENY PREEMPTIVE RIGHTS TO ITS
SHAREHOLDERS. A FULL STATEMENT OF SUCH LIMITATION IS SET FORTH IN THE ARTICLES
OF INCORPORATION ON FILE IN THE OFFICE OF THE SECRETARY OF STATE OF THE STATE OF
TEXAS. THE CORPORATION WILL FURNISH A COPY OF SUCH STATEMENT TO THE HOLDER OF
THIS CERTIFICATE WITHOUT CHARGE ON REQUEST TO THE CORPORATION AT ITS PRINCIPAL
PLACE OF BUSINESS OR REGISTERED OFFICE.

         7. SECURITIES LAW REQUIREMENTS. The Optionee agrees and understands
that the Shares may be restricted securities as defined in Rule 144 promulgated
under the Securities Act of 1933, as amended (the "Securities Act"), and may not
be sold, assigned or transferred, unless the sale, assignment or transfer of
such shares is registered under the Securities Act and applicable blue sky laws,
as now in effect or hereafter amended, or there is furnished an opinion of
counsel in form and substance satisfactory to the Company from counsel
acceptable to the Company that such registrations are not required.

         8. NO RIGHTS AS SHAREHOLDER. The Optionee shall not have any rights as
a shareholder with respect to any of the Shares until the date of issuance by
the Company to the Optionee of a stock certificate representing such Shares
pursuant to Section 6 hereof. Except as otherwise provided in Section 9 hereof,
the Optionee shall not be entitled to any dividends, cash or otherwise, or any
adjustment of the Shares for such dividends, if the record date therefor is
prior to the date of issuance of such stock certificate.

         9. CORPORATE PROCEEDINGS OF THE COMPANY.

                  (a) The existence of the Option shall not affect in any way
         the right or power of the Company or its officers, directors and
         shareholders, as the case may be, to (i) make or authorize any
         adjustments, recapitalizations, reorganizations or other changes in the
         capital structure or business of the Company, (ii) participate in any
         merger or consolidation of the


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         Company, (iii) issue any Common Stock, bonds, debentures, preferred or
         prior preference stock or any other securities affecting the Common
         Stock or the rights of holders thereof, (iv) dissolve or liquidate the
         Company, (v) sell or transfer all or any part of the assets or business
         of the Company, or (vi) perform any other corporate act or proceedings,
         whether of a similar character or otherwise.

                  (b) If the Company merges into or with or consolidates with
         (such events collectively referred herein as a "Merger") any
         corporation or corporations or entity or entities and is not the
         surviving corporation, then the surviving corporation may assume the
         Option or substitute a new option of the surviving corporation for the
         Option; provided, however, that the excess of the aggregate fair market
         value of the securities subject to the Option immediately after such
         assumption, or the new option immediately after such substitution, over
         the aggregate exercise price of such shares must be, based upon a good
         faith determination by the Board of Directors of the Company, not less
         than the excess of the aggregate fair market value of the Common Stock
         subject to the Option immediately before such substitution or
         assumption over the aggregate exercise price of such Common Stock.

                  (c) In the event that the surviving corporation does not
         utilize the provisions of (b) above, or in the event of a dissolution
         or liquidation of the Company, the Company shall cause written notice
         of such Merger or dissolution or liquidation (and the material terms
         and conditions thereof) to be delivered to the Optionee at least ten
         (10) days prior to the proposed effective date (the "Effective Date")
         of such event. The Optionee shall be entitled to exercise the option
         (as to all Option Shares whether or not the Option is then otherwise
         exercisable under Section 2) until the Effective Date, or until the
         Expiration Date, if earlier. To the extent that the Merger or
         liquidation is consummated after the Effective Date, the Option shall
         terminate and the Company shall have no further obligations of any type
         hereunder. The provisions of this paragraph shall not apply to any
         merger or reorganization, the principal purpose of which is to change
         the jurisdiction of the domicile of the Company.

                  (d) If, while the Option is outstanding, the Company shall
         effect a subdivision or consolidation of the shares of Common Stock or
         other capital readjustment, the payment of a common stock dividend, or
         other increase or reduction of the number of shares of Common Stock
         outstanding, without receiving compensation therefor in money, services
         or property, then (i) in the event of an increase in the number of
         shares of Common Stock outstanding, the number of Shares shall be
         proportionately increased, and the per share exercise price shall be
         proportionately reduced, and (ii) in the event of a reduction in the
         number of shares of Common Stock outstanding, the number of Shares
         shall be proportionately reduced, and the per share exercise price
         shall be proportionately increased. No fractional share of Common Stock
         shall be issued upon any such exercised and the exercise price shall be
         appropriately reduced on account of any fractional share not issued.

                  (e) The issuance by the Company of shares of stock of any
         class of securities convertible into shares of stock of any class,
         including Common Stock, for cash, property,


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         labor or services rendered, either upon direct sale or upon the
         exercise of rights, options, or warrants to subscribe therefor, or upon
         conversion of shares or obligations of the Company convertible into
         such shares or other securities, shall not affect, and no adjustment by
         reason thereof shall be made with respect to, the number of Shares or
         the exercise price thereof.

         10. REGISTRATION RIGHTS. The Optionee shall have no registration rights
with respect to the Shares.

         11. TERMINATION. Except as otherwise provided in Section 9(c) hereof,
this Option, to the extent not previously exercised, shall terminate on the
earliest of the following to occur:

                  (a) on the last day of the three-month period commencing on
         the date on which the Optionee ceases to be a member of the Company's
         board of directors, for any reason other than death of the Optionee,
         during which period the Optionee shall be entitled to exercise all or
         any portion of this Option held by Optionee on the date of such
         cessation, to the extent such Option was exercisable by Optionee on
         such date of such cessation, and subject to the provisions of Section 3
         hereof;

                  (b) on the last day of the one year period commencing on the
         date of the Optionee's death while serving as a member of the Company's
         board of directors, during which period the executor or administrator
         of the Optionee's estate or the person or persons to whom the Optionee
         shall have transferred all or any portion of this Option by will or the
         laws of descent and distribution, shall be entitled to exercise all or
         any portion of the respective Option, to the extent such Option would
         have been exercisable by Optionee on the date of his or her death, and
         subject to the provisions of Section 3 hereof; or

                  (c) ten years after the Grant Date.

                  (d) Notwithstanding the foregoing, the Optionee may exercise
         the Option as to all of the Option Shares (whether previously
         exercisable or not) on or before one (1) year after a Change of Control
         of the Corporation shall be deemed to have occurred.

                  For the purposes of this Agreement, a "Change of Control of
         the Corporation" shall be deemed to have occurred if after the
         effective date of this Agreement (i) any "person" (as such term is used
         in Sections 13(d) and 14(d) of the Act) is or becomes the "beneficial
         owner" (as defined in Rule 13d-3 under the Securities Exchange Act of
         1934 [the "Act"]), directly or indirectly, or securities of the
         Corporation representing 50% or more of the combined voting power of
         the Corporation's then outstanding securities; (ii) there occurs a
         proxy contest or a consent solicitation, or the Corporation is a party
         to a merger, consolidation, sale of assets, plan of liquidation or
         other reorganization as a consequence of which members of the Board of
         Directors in office immediately prior to such transaction or event
         constitute less than a majority of the Board of Directors thereafter;
         or (iii) during any period of two consecutive years, other than as a
         result of an event described in clause (ii) of this paragraph,
         individuals who at the


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         beginning of such period constituted the Board of Directors (including
         for this purpose any new director whose election or nomination for
         election by the Corporation's stockholders was approved by a vote of at
         least a majority of the directors then still in office who were
         directors at the beginning of such period) cease for any reason to
         constitute at least a majority of the Board of Directors.

                  Nothing in (a), (b), (c) or (d) shall extend the time for
         exercising the Option granted pursuant to this Agreement beyond the
         Expiration Date.

         12. TERM OF DIRECTORSHIP. This Option shall not grant to Optionee any
right to continue serving as a member of the Company's board of directors.

         13. INDEPENDENT LEGAL AND TAX ADVICE. The Optionee has been advised and
been provided the opportunity to obtain independent legal and tax advice
regarding the grant and exercise of this Option and the disposition of any
Shares acquired thereby.

         14. AMENDMENT. This Agreement may not be amended, modified or waived
except by a written instrument signed by the party against whom enforcement of
any such modification, amendment or waiver is sought.

         15. GOVERNING LAW. This Agreement shall be governed by and shall be
construed and enforced in accordance with the laws of the State of Texas.

         16. NOTICES. All notices, requests, demands or other communications
permitted to be given hereunder shall be in writing and shall be deemed property
given or made when personally delivered to an officer of the Company or to the
Optionee, as the case may be, or if mailed when deposited in the United States
mails by certified or registered mail, return receipt requests, postage prepaid,
and addressed to the address set forth for each party on the signature page
hereto. Any party may change its address by giving notice in writing to the
other party stating the new address, and such change will be effective
immediately upon receipt of such notice.

         17. COUNTERPARTS. This Agreement may be executed in two or more
counterparts by original or facsimile signature, each of which shall be deemed
an original and all of which together shall constitute one and the same
instrument.

                            [SIGNATURE PAGE FOLLOWS]

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         IN WITNESS WHEREOF, the Company and the Optionee have caused this
Agreement to be duly executed as of the date first above written.


                                            GREY WOLF, INC.



                                            By: /s/ David W. Wehlmann
                                                -------------------------------
                                                     David W. Wehlmann
                                                     Senior Vice President and
                                                     Chief Financial Officer


                                            Address:      Grey Wolf, Inc.
                                                          10370 Richmond,
                                                          Suite 600
                                                          Houston, Texas 77042
                                                          Attn: President

                                            Facsimile:    713-435-6171




                                            OPTIONEE:

                                            /s/ Robert E. Rose
                                            -----------------------------------
                                            Robert E. Rose
                                            Global Marine Inc.
                                            777 North Eldridge Parkway
                                            Houston, Texas 77079




                                            Facsimile:    281-596-5142