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                                                                   EXHIBIT 10.10

                              MARINER ENERGY, INC.
                            EQUITY PARTICIPATION PLAN

SECTION 1. PURPOSE OF THE PLAN

     The Mariner Energy, Inc. Equity Participation Plan (the "Plan") is intended
to promote the interests of Mariner Energy, Inc., a Delaware corporation (the
"Company"), by granting certain Employees an equity interest in the Company and
providing a means whereby they may develop a sense of proprietorship and
personal involvement in the development and financial success of the Company,
and to encourage them to remain with and devote their best efforts to the
business of the Company, thereby advancing the interests of the Company and its
stockholders.

SECTION 2. DEFINITIONS

     As used in the Plan, the following terms shall have the meanings set forth
below:

     "Award" shall mean Restricted Stock.

     "Award Agreement" shall mean any written or electronic agreement, contract,
instrument or document evidencing any Award, which may, but need not, be
executed or acknowledged by a Participant.

     "Board" shall mean the Board of Directors of the Company.

     "Code" shall mean the Internal Revenue Code of 1986, as amended from time
to time, and the rules and regulations thereunder.

     "Committee" shall mean the Board or any committee of the Board designated,
from time to time, by the Board to act as the Committee under the Plan.

     "Effective Date" shall mean March 11, 2005.

     "Employee" shall mean any employee of the Company.

     "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended.

     "Fair Market Value" shall mean, as of any applicable date, the last
reported sales price for a Share on the principal securities exchange on which
the Shares are traded on the applicable date as reported by such reporting
service approved by the Committee; provided, however, that if Shares shall not
have been quoted or traded on such applicable date, Fair Market Value shall be
determined based on the next preceding date on which they were quoted or traded,
or, if deemed appropriate by the Committee, in such other manner as it may
determine to be appropriate. In the event the Shares are not publicly traded at
the time a determination of its Fair Market Value is required to be made
hereunder, the determination of Fair Market Value shall be made in good faith by
the Committee.

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     "Parent Entity" means any entity that owns a majority of the voting power
of the Company, directly or indirectly.

     "Participant" shall mean any Employee granted an Award under the Plan.

     "Person" shall mean individual, corporation, partnership, limited liability
company, association, joint-stock company, trust, unincorporated organization,
government or political subdivision thereof or other entity.

     "Restricted Period" shall mean the period established by the Committee with
respect to an Award during which the Award either remains subject to forfeiture
or is not exercisable by the Participant.

     "Restricted Stock" shall mean any Share, prior to the lapse of restrictions
thereon, granted under Section 6(a) of the Plan.

     "Rule 16b-3" shall mean Rule 16b-3 promulgated by the SEC under the
Exchange Act, or any successor rule or regulation thereto as in effect from time
to time.

     "SEC" shall mean the Securities and Exchange Commission, or any successor
thereto.

     "Shares" or "Common Shares" or "Common Stock" shall mean the common stock
of the Company, $.0001 par value, and such other securities or property as may
become the subject of Awards of the Plan.

     "Subsidiary" shall mean any entity (whether a corporation, partnership,
joint venture, limited liability company or other entity) in which the Company
owns a majority of the voting power of the entity directly or indirectly.

SECTION 3. ADMINISTRATION.

     The Plan shall be administered by the Committee. A majority of the
Committee shall constitute a quorum, and the acts of the members of the
Committee who are present at any meeting thereof at which a quorum is present,
or acts unanimously approved by the members of the Committee in writing, shall
be the acts of the Committee. Subject to the terms of the Plan and applicable
law, and in addition to other express powers and authorizations conferred on the
Committee by the Plan, the Committee shall have full power and authority to: (i)
designate Participants; (ii) determine the number of Shares to be covered by, or
with respect to which payments, rights, or other matters are to be calculated in
connection with, Awards; (iii) determine the terms and conditions of any Award;
(iv) interpret and administer the Plan and any instrument or agreement relating
to an Award made under the Plan; (v) establish, amend, suspend, or waive such
rules and regulations and appoint such agents as it shall deem appropriate for
the proper administration of the Plan; and (vi) make any other determination and
take any other action that the Committee deems necessary or desirable for the
administration of the Plan. Unless otherwise expressly provided in the Plan, all
designations, determinations, interpretations, and other decisions under or with
respect to the Plan or any award shall be within the sole discretion of the
Committee, may be made at any time and shall be final, conclusive, and binding


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upon all Persons, including the Company, any Subsidiary, any Parent Entity, any
Participant, any holder or beneficiary of any Award, any stockholder and any
other Person.

SECTION 4. SHARES AVAILABLE FOR AWARDS.

     (a) Shares Available. Subject to adjustment as provided in Section 4(c),
the number of Shares that may be issued with respect to Awards granted under the
Plan shall be 2,267,270. If an Award is forfeited or otherwise lapses, expires,
terminates or is canceled without the actual delivery of Shares, then the Shares
covered by such Award, to the extent of such forfeiture, expiration, lapse,
termination or cancellation, shall not again be Shares that may be issued with
respect to Awards granted under the Plan.

     (b) Sources of Shares Deliverable Under Awards. Any Shares delivered
pursuant to an Award may consist, in whole or in part, of authorized and
unissued Shares or of treasury Shares.

     (c) Adjustments. In the event of a stock dividend or stock split with
respect to Shares, the number of Shares with respect to which Awards may be
granted, the number of Shares subject to outstanding Awards automatically shall
be proportionately adjusted, without action by the Committee which adjustment
will be evidenced by written addendums to the Plan and Award Agreements prepared
by the Company.

SECTION 5. ELIGIBILITY.

     Any Employee shall be eligible to be designated a Participant by the
Committee.

SECTION 6. AWARDS.

     (a) Restricted Stock. Awards of Restricted Stock with respect to the total
number of Shares that may be issued under the Plan shall be granted on the
Effective Date, and, subject to the provisions of the Plan, the Committee shall
have the authority to determine the Participants to whom Restricted Stock shall
be granted, the number of Shares of Restricted Stock to be granted to each such
Participant, the duration of the Restricted Period, the conditions under which
the Restricted Stock may be forfeited to the Company, and the other terms and
conditions of such Awards.

          (i) Dividends. Dividends paid on Restricted Stock may be paid directly
     to the Participant, may be subject to risk of forfeiture and/or transfer
     restrictions during any period established by the Committee or sequestered
     and held in a bookkeeping cash account (with or without interest) or
     reinvested on an immediate or deferred basis in additional shares of Common
     Stock, which credit or shares may be subject to the same restrictions as
     the underlying Award or such other restrictions, all as determined by the
     Committee in its discretion, as provided in the Award Agreement.

          (ii) Registration. Any Restricted Stock may be evidenced in such
     manner as the Committee shall deem appropriate, including, without
     limitation, book-entry registration or issuance of a stock certificate or
     certificates. In the event any stock certificate is issued in respect of
     Restricted Stock granted under the Plan, such certificate


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     shall be registered in the name of the Participant and shall bear an
     appropriate legend referring to the terms, conditions, and restrictions
     applicable to such Restricted Stock.

          (iii) Forfeiture and Restrictions Lapse. Except as otherwise
     determined by the Committee or the terms of the Award Agreement that
     granted the Restricted Stock, upon the termination of a Participant's
     employment for any reason during the applicable Restricted Period, all
     Restricted Stock shall be forfeited by the Participant without payment and
     re-acquired by the Company. The Committee may, when it finds that a waiver
     would be in the best interests of the Company, waive in whole or in part
     any or all remaining restrictions with respect to such Participant's
     Restricted Stock.

          (iv) Transfer Restrictions. During the Restricted Period, Restricted
     Stock will be subject to such limitations on transfer as necessary to
     comply with Section 83 of the Code.

     (b) General.

          (i) Awards May Be Granted Separately or Together. Awards may, in the
     discretion of the Committee, be granted either alone or in addition to, in
     tandem with, any award granted under any other plan of the Company or any
     Parent Entity or Subsidiary. Awards granted in addition to or in tandem
     with other awards granted under any other plan of the Company or any Parent
     Entity or Subsidiary may be granted either at the same time as or at a
     different time from the grant of such other Awards or awards.

          (ii) Limits on Transfer of Awards. No Award and no right under any
     such Award may be assigned, alienated, pledged, attached, sold or otherwise
     transferred or encumbered by a Participant other than by will or by the
     laws of descent and distribution, and any such purported prohibited
     assignment, alienation, pledge, attachment, sale, transfer or encumbrance
     shall be void and unenforceable against the Company or any Parent Entity or
     Subsidiary. To the extent specifically approved in writing by the
     Committee, an Award may be transferred to immediate family members or
     related family trusts, limited partnerships or similar entities or other
     Persons on such terms and conditions as the Committee may establish or
     approve in its sole discretion.

          (iii) Terms of Awards. The terms of each Award shall be as determined
     by the Committee.

          (iv) Share Restrictions. All Shares or other securities of the Company
     delivered under the Plan pursuant to any Award shall be subject to such
     stop transfer orders and other restrictions as the Committee may deem
     advisable under the Plan or the rules, regulations, and other requirements
     of the SEC, any stock exchange upon which such Shares or other securities
     are then listed, and any applicable federal or state laws, and, if
     certificates are issued for the Shares, the Committee may cause a legend or
     legends to be put on any such certificates to make appropriate reference to
     such restrictions.


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          (v) Consideration for Grants. Awards may be granted for no cash
     consideration or for such consideration as the Committee determines
     including, without limitation, such minimal cash consideration as may be
     required by applicable law.

          (vi) Delivery of Shares or other Securities and Payment by Participant
     of Consideration. No Shares or other securities shall be delivered pursuant
     to any Award until payment in full of any amount required to be paid
     pursuant to the Plan or the applicable Award Agreement (including, without
     limitation, any tax withholding) is received by the Company. Such payment
     may be made by such method or methods and in such form or forms as the
     Committee shall determine, including, without limitation, cash, Shares,
     other securities, or other property, withholding of Shares, or any
     combination thereof, provided that the combined value, as determined by the
     Committee, of all cash and cash equivalents and the Fair Market Value of
     any such Shares or other property so tendered to the Company, as of the
     date of such tender, is at least equal to the full amount required to be
     paid pursuant to the Plan or the applicable Award Agreement to the Company.

          (vii) Unusual Transactions or Events. In the event of any distribution
     (whether in the form of cash, Shares, other securities, or other property),
     recapitalization, reorganization, merger, spin-off, split-off, split-up,
     consolidation, combination, repurchase, or exchange of Shares or other
     securities of the Company, or other relevant corporate transaction or event
     or any unusual or nonrecurring transactions or events affecting the
     Company, or any affiliate of the Company, and whenever the Committee
     determines that action is appropriate in order to prevent the dilution or
     enlargement of the benefits or potential benefits intended to be made
     available under the Plan or with respect to any Award under the Plan, to
     facilitate such transactions or events, the Committee, in its sole
     discretion and on such terms and conditions as it deems appropriate, may
     take any one or more of the following actions:

               (A) To provide that such Award be assumed by the successor or
          survivor corporation, or a parent or subsidiary thereof, or shall be
          substituted for by similar rights or awards covering the stock of the
          successor or survivor corporation, or a parent or subsidiary thereof,
          with appropriate adjustments as to the number and kind of shares; and

               (B) To provide that such Award shall be payable or fully vested
          with respect to all Shares covered thereby, notwithstanding anything
          to the contrary in the Plan or the applicable Award Agreement.

SECTION 7. AMENDMENT.

     Except to the extent prohibited by applicable law and unless otherwise
expressly provided in an Award Agreement or in the Plan:

          (i) Amendments to the Plan. The Board or the Committee may amend or
     alter the Plan without the consent of any stockholder, Participant, other
     holder or beneficiary of an Award, or other Person; provided, however, that
     no such amendment or


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     alteration shall materially adversely affect the rights of a Participant
     under an Award without the consent of such Participant.

          (ii) Amendments to Awards. Subject to clause (i) above, the Committee
     may waive any conditions or rights under, amend any terms of, or alter any
     Award theretofore granted, provided no change in any Award shall materially
     adversely affect the rights of a Participant under the Award without the
     consent of such Participant.

          (iii) Compliance with Applicable Law. Notwithstanding the foregoing,
     the Committee may make any amendment to the Plan or an Award Agreement that
     it believes necessary or helpful to comply with any applicable law,
     including without limitation, Section 409A of the Code.

SECTION 8. GENERAL PROVISIONS.

     (a) No Rights to Awards. No Participant or other Person shall have any
claim to be granted any Award, there is no obligation for uniformity of
treatment of Participants, or holders or beneficiaries of Awards and the terms
and conditions of Awards need not be the same with respect to each recipient.

     (b) No Right to Employment or Retention. The grant of an Award shall not be
construed as giving a Participant the right to be retained in the employ of the
Company or any Parent Entity or Subsidiary or under any other service contract
with the Company or any Parent Entity or Subsidiary. Further, the Company or a
Parent Entity or Subsidiary may at any time dismiss a Participant from
employment free from any liability or any claim under the Plan, unless otherwise
expressly provided in the Plan, in any Award Agreement or any other agreement or
contract between the Company or a Parent Entity or Subsidiary and the affected
Participant. If a Participant's employer was a Parent Entity or Subsidiary and
ceases to be a Parent Entity or Subsidiary, such Participant shall be deemed to
have terminated employment for purposes of the Plan, unless specifically
provided otherwise in the Award Agreement.

     (c) Governing Law. The validity, construction, and effect of the Plan and
any rules and regulations relating to the Plan shall be determined in accordance
with the laws of the State of Texas and applicable federal law.

     (d) Severability. If any provision of the Plan or any Award is or becomes
or is deemed to be invalid, illegal, or unenforceable in any jurisdiction or as
to any Person or Award, or would disqualify the Plan or any Award under any law
deemed applicable by the Committee, such provision shall be construed or deemed
amended to conform to the applicable laws, or if it cannot be construed or
deemed amended without, in the determination of the Committee, materially
altering the intent of the Plan or the Award, such provision shall be stricken
as to such jurisdiction, Person or Award and the remainder of the Plan and any
such Award shall remain in full force and effect.

     (e) Other Laws. The Committee may refuse to issue or transfer any Shares or
other consideration under an Award, permit the exercise of an Award and/or the
satisfaction of its tax withholding obligation in the manner elected by the
Participant, holder or beneficiary if, acting in its sole discretion, it
determines that the issuance of transfer or such Shares or such other


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consideration, the manner of exercise or satisfaction of the tax withholding
obligation might violate any applicable law or regulation, including without
limitation, the Sarbanes-Oxley Act, or entitle the Company to recover the same
under Section 16(b) of the Exchange Act, and any payment tendered to the Company
by a Participant, other holder or beneficiary in connection with the exercise of
such Award shall be promptly refunded or refused, as the case may be, to the
relevant Participant, holder or beneficiary.

     (f) No Trust or Fund Created. Neither the Plan nor the Award shall create
or be construed to create a trust or separate fund of any kind or a fiduciary
relationship between the Company or any Parent Entity or Subsidiary and a
Participant or any other Person. To the extent that any Person acquires a right
to receive payments from the Company or any Parent Entity or Subsidiary pursuant
to an Award, such right shall be no greater than the right of any general
unsecured creditor of the Company or any Parent Entity or Subsidiary.

     (g) No Fractional Shares. No fractional Shares shall be issued or delivered
pursuant to the Plan or any Award, and the Committee shall determine whether
cash, other securities, or other property shall be paid or transferred in lieu
of any fractional Shares or whether such fractional Shares or any rights thereto
shall be cancelled, terminated, or otherwise eliminated.

     (h) Headings. Headings are given to the Section and subsections of the Plan
solely as a convenience to facilitate reference. Such headings shall not be
deemed in any way material or relevant to the construction or interpretation of
the plan or any provision thereof.

SECTION 9. EFFECTIVE DATE OF AND TERM OF THE PLAN.

     The Plan shall become effective as of the Effective Date. Further, no
Awards may be made after the Effective Date. However, unless otherwise expressly
provided in the Plan or in an applicable Award Agreement, the Plan shall remain
in effect until all Awards granted under the Plan have vested or been forfeited.


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