Exhibit
        10.24
 
 PLATINUM
        UNDERWRITERS HOLDINGS, LTD.
 RETENTION
        BONUS PLAN
  The
        Company hereby adopts this Platinum Underwriters Holdings, Ltd. Retention
        Bonus
        Plan for the benefit of certain employees of the Company and its subsidiaries,
        on the terms and conditions hereinafter stated, effective as of April 27,
        2007.  The Plan, as set forth herein, is intended to ensure employees’
continued dedication and efforts, to help retain qualified employees and
        to
        maintain a stable work environment.  All capitalized terms used in
        this Plan or in an Award Letter are defined herein.
  SECTION
                  1.
              DEFINITIONS.
  As
        hereinafter used:
  1.1  “AIP”
means
        the
        Platinum Underwriters Holdings, Ltd. Amended and Restated Annual Incentive
        Plan,
        effective January 1, 2006, as amended from time to time.
  1.2  “Award
        Letter” has the
        meaning specified in Section 2.1 of the Plan.
  1.3  “Board”
means
        the
        Board of Directors of the Company.
  1.4  “Cause”
shall
        have the
        meaning given to such term in any employment or severance agreement between
        the
        Company and the Participant as in effect at the time of termination of
        employment.  In the event that no such agreement is in effect, “Cause”
shall mean (i) the willful failure by the Participant to perform substantially
        the Participant’s duties to the Company or any subsidiary of the Company (other
        than due to death or disability) after reasonable notice to the Participant
        of
        such failure; (ii) the Participant’s engaging in misconduct that is injurious to
        the Company or any subsidiary of the Company, including, without limitation,
        by
        way of damage to business reputation or industry standing; (iii) the Participant
        having been convicted of, or having entered a plea of nolocontendere
        to, a crime that
        constitutes a felony, (iv) the Participant’s breach of any restrictive covenants
        agreed to between the Participant and the Company or any subsidiaries of
        the
        Company; or (v) the Participant’s termination for “cause” as defined under any
        other plan of the Company or any agreement between the Participant and the
        Company.
  1.5  “Change
        in Control”
shall have the meaning specified in Section 10.2 of the Platinum Underwriters
        Holdings, Ltd. 2006 Share Incentive Plan, as amended from time to
        time.
  1.6  “Code”
means
        the
        Internal Revenue Code of 1986, as it may be amended from time to time, including
        any rules and regulations promulgated thereunder, along with Treasury and
        IRS
        interpretations thereof.  Reference to any section or subsection of
        the Code includes reference to any comparable or succeeding provisions of
        any
        legislation that amends, supplements or replaces such section or
        subsection.
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 1.7  “Company”
means
        Platinum Underwriters Holdings, Ltd., a company organized under the laws
        of
        Bermuda, and its successors.
  1.8  “Committee”
means
        the
        Compensation Committee of the Board.
  1.9  “Disability”
means
        a
        Participant being considered “disabled” within the meaning of Section
        409A(a)(2)(C) of the Code.
  1.10  “Exchange
        Act” means
        the Securities Exchange Act of 1934, as amended.
  1.11  “Good
        Reason” shall
        have the meaning given to such term in any employment or severance agreement
        between the Company and the Participant as in effect at the time of termination
        of employment.  In the event that no such agreement is in effect,
“Good Reason”
        shall mean, on or following a Change in Control, (a) a reduction in the
        Participant’s annual base salary or (b) the relocation of the Participant’s
        principal place of employment to a location more than 50 miles from his or
        her
        principal place of employment immediately prior to the Change in
        Control.
  1.12  “Participant”
means
        any employee of the Company (or any of its subsidiaries or affiliates)
        designated as a Participant by the Chief Executive Officer of the Company
        to
        participate in the Plan.
  1.13  “Plan”
means
        this
        Platinum Underwriters Holdings, Ltd. Retention Bonus Plan, as it may be amended
        from time to time.
  1.14  “Plan
        Administrator”
means the person or persons appointed from time to time by the Committee
        to
        administer this Plan which appointment may be revoked at any time by the
        Committee.
  1.15  “Retention
        Bonus
        Award” means an amount designated in a Participant’s Award
        Letter.
  1.16  “Payment
        Trigger Date”
means the earlier of:  (a) the date on which a Change in Control is
        consummated or (b) March 31, 2008.
   SECTION
                  2.
              PARTICIPATION
  2.1  Each
        Participant shall be advised in writing that he or she has been designated
        as a
        Participant by an award letter signed or specifically authorized to be signed
        by
        the Plan Administrator (such instrument, an “Award
        Letter”).  Each Award Letter shall so advise the recipient that
        he or she has been designated as a Participant in the Plan and shall be eligible
        to receive the Retention Bonus Award in the amount specified in the Award
        Letter.  No employee will at any time have the right to be selected as
        a Participant.
  2.2  Retention
        Bonus Awards made under the Plan are not in lieu of any other benefits a
        Participant may be entitled to receive from the Company.  Retention
        Bonus Awards will not be considered compensation for purposes of the Company’s
        welfare benefit plans, programs and arrangements.
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  SECTION
                  3.
              RETENTION
                  BONUS AWARD.
  3.1  Except
        as
        provided in this Section 3, a Participant shall be entitled to receive the
        Participant’s Retention Bonus Award so long as the Participant continues to be
        employed by the Company on payment date of such Retention Bonus Award, as
        specified in Section 3.4.
  3.2  If
        a
        Participant’s employment is terminated prior to the Payment Trigger Date for any
        reason (other than the Participant’s death or Disability), the Participant will
        not be entitled to the Retention Bonus Award.  In the event of
        termination of the Participant’s employment as a result of the Participant’s
        death or Disability, the Participant or the Participant’s legal representative
        will nonetheless be entitled to receive the Participant’s Retention Bonus Award
        on the payment date, as specified in Section 3.4.
  3.3  Notwithstanding
        anything in Section 3.1 to the contrary, to the extent on or following the
        Payment Trigger Date and prior to payment of the Participant’s Retention Bonus
        Award, (a) the Participant’s employment is terminated by the Company without
        Cause, (b) the Participant resigns employment with the Company for Good Reason,
        (c) the Participant’s termination of employment as a result of the Participant’s
        death or (d) the Participant termination of employment as a result of the
        Participant’s Disability, the Participant (or in the event of death or
        Disability, the Participant’s legal representative) will nonetheless be entitled
        to receive the Participant’s Retention Bonus Award on the payment date, as
        specified in Section 3.4.
  3.4  Subject
        to Section 6 of the Plan, a Participant's Retention Bonus Award shall be
        paid in
        a single lump-sum payment to the Participant on March 31, 2008.
  SECTION
                  4.
              PLAN
                  ADMINISTRATION.
  4.1  The
        Plan
        Administrator will administer the Plan and may interpret the Plan, prescribe,
        amend and rescind rules and regulations under the Plan and make all other
        determinations necessary or advisable for the administration of the Plan,
        subject to all of the provisions of the Plan; provided, however,
        that the
        Chief Executive Officer will be the Plan Administrator with respect to any
        person appointed as the Plan Administrator who is a Participant in the
        Plan.  Any determination by the Plan Administrator hereunder will be
        conclusive, but however, will not be entitled to deference by a trier of
        fact.  The Plan Administrator may delegate any of its duties hereunder
        to such person or persons from time to time as it may designate.
  4.2  The
        Plan
        Administrator is empowered, on behalf of the Plan, to engage accountants,
        legal
        counsel and such other personnel as it deems necessary or advisable to assist
        it
        in the performance of its duties under the Plan.  The functions of any
        such persons engaged by the Plan Administrator will be limited to the specified
        services and duties for which they are engaged, and such persons will have
        no
        other duties, obligations or responsibilities under the Plan.  Such
        persons will exercise no discretionary authority or discretionary control
        respecting the management of the Plan.  All reasonable expenses
        thereof will be borne by the Company.
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  SECTION
                  5.
              PLAN
                  MODIFICATION OR TERMINATION.
  At
        any
        time prior to the Payment Trigger Date, the Plan may be amended or terminated
        by
        the Board at any time with respect to any or all Participants; provided, however,
        that,
        subject to Section 6 of the Plan, no termination or amendment may reduce
        the
        benefits or payments under the Plan to a Participant or otherwise be adverse
        in
        any manner to the interests of any Participant.
  SECTION
                  6.
              COMPLIANCE
                  WITH SECTION 409A OF THE CODE.
  6.1  To
        the
        extent applicable, it is intended that this Plan and any awards made hereunder
        are exempt from Section 409A of the Code or are structured in a manner that
        would not cause a Participant to be subject to taxes and interest pursuant
        to
        Section 409A of the Code.  This Plan and any award made hereunder
        shall be administered in a manner consistent with this intent, and any provision
        that would cause this Plan or any award made hereunder to become subject
        to
        taxation under Section 409A of the Code shall have no force and effect until
        amended to comply with Section 409A of the Code (which amendment may be
        retroactive to the extent permitted by Section 409A of the Code and may be
        made
        by the Company without the consent of Participants).
  6.2  Notwithstanding
        any provision of this Plan to the contrary, to the extent an award shall
        be
        deemed to be vested (i) upon the occurrence of a Change in Control and (ii)
        in
        accordance with the payment provisions of Section 3 of the Plan, and such
        Change
        in Control does not constitute a “change in the ownership or effective control”
or a “change in the ownership or a substantial portion of the assets” of the
        Company within the meaning of Section 409A(a)(2)(A)(v) of the Code, then
        even
        though such award may be deemed to be vested upon the occurrence of the Change
        in Control or any other provision of this Plan, payment will be made, to
        the
        extent necessary to comply with the provisions of Section 409A of the Code,
        to
        the Participant on the earliest of:  (i) the Participant’s “separation
        from service” with the Company (determined in accordance with Section 409A of
        the Code); provided, however,
        that if the
        Participant is a “specified employee” (within the meaning of Section 409A of the
        Code), the payment date shall be the date that is six (6) months after the
        date
        of the Participant’s separation from service with the Company, (ii) March 31,
        2008, or (iii) the Participant’s death.
  SECTION
                  7.
              GENERAL
                  PROVISIONS.
  7.1  Except
        as
        otherwise provided herein or by law, no right or interest of any Participant
        under the Plan will be assignable or transferable, or otherwise encumbered
        in
        whole or in part, either directly or by operation of law or otherwise, including
        without limitation by execution, levy, garnishment, attachment, pledge or
        in any
        manner.  No attempted assignment or transfer thereof will be
        effective, and no right or interest of any Participant under the Plan will
        be
        liable for, or subject to, any obligation or liability of such
        Participant.
  7.2  Neither
        the establishment of the Plan, nor any modification thereof, nor the creation
        of
        any fund, trust or account, nor the payment of any benefits will be construed
        as
        giving any Participant, or any person whomsoever, the right to be retained
        in
        the service of the Company or any subsidiary or affiliate of the
        Company.
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 7.3  If
        any
        provision of this Plan is held invalid or unenforceable, such invalidity
        or
        unenforceability will not affect any other provisions hereof, the remainder
        of
        this Plan and the application of such provision to any other person or
        circumstance will not be affected, and the provision so held to be invalid
        or
        unenforceable will be reformed to the extent (and only to the extent) necessary
        to make it enforceable or valid.  To the extent any provisions held to
        be invalid or unenforceable cannot be reformed, such provisions are to be
        stricken herefrom and the remainder of this Plan will be binding on the parties
        and their successors and assigns as if such invalid or unenforceable provisions
        were never included in this Plan from the first instance.
  7.4  This
        Plan
        will inure to the benefit of and be binding upon the heirs, executors,
        administrators, successors and assigns of the parties, including each
        Participant, present and future, and any successor to the Company, including
        any
        persons acquiring directly or indirectly all or substantially all of the
        business or assets of the Company whether by purchase, merger, consolidation,
        reorganization or otherwise (and such successor will thereafter be deemed
        the
“Company” for the purposes of this Plan).
  7.5  The
        headings and captions herein are provided for reference and convenience only,
        will not be considered part of the Plan, and will not be employed in the
        construction of the Plan.
  7.6  The
        Plan
        will not be funded.  No Participant will have any right to, or
        interest in, any assets of any Company which may be applied by the Company
        to
        the payment of benefits or other rights under this Plan.
  7.7  Any
        notice or other communication required or permitted pursuant to the terms
        hereof
        shall have been duly given when delivered or mailed by United States Mail,
        first
        class, postage prepaid, addressed to the intended recipient at his, her or
        its
        last known address.
  7.8  This
        Plan
        will be governed by and construed in accordance with the internal substantive
        laws of theState
        of New York.
  7.9  The
        Company will deduct from all amounts paid pursuant to the terms of the Plan,
        all
        federal, state, local and other taxes that the Company is required by law
        to
        withhold with respect to such amounts pursuant to applicable law, and such
        amounts will be subject to applicable tax reporting, as determined by the
        Plan
        Administrator.
  7.10  No
        member
        of the Board or the Committee or any officer, or employee of the Company
        will be
        personally liable by reason of any contract or other instrument, or any action
        or inaction, related to the Plan or any Award Letter and the Company will
        indemnify and hold harmless each such person against any cost or expense
        (including legal fees, disbursements and other related fraud charges) or
        liability (including any sum paid in settlement) arising out of any of the
        foregoing.
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