EXHIBIT 10.3 WAIVER AND CONSENT

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                                                                    EXHIBIT 10.3

                               WAIVER AND CONSENT

      This Waiver and Consent ("Agreement") dated as of December 29, 2004

("Effective Date") is among Mariner Energy, Inc., a Delaware corporation (the

"Borrower"), Mariner Holdings, Inc. and Mariner Energy, LLC, the Lenders (as

defined below), and Union Bank of California, N.A., as administrative agent for

such Lenders (in such capacity, the "Administrative Agent") and as issuing

lender for such Lenders (in such capacity, the "Issuing Lender").

                                    RECITALS

      A.     The Borrower, the Lenders, Issuing Lender and the Administrative

Agent are parties to the Credit Agreement dated as of March 2, 2004, as amended

by that certain Amendment No. 1 and Assignment Agreement dated as of July 14,

2004 (as so amended, the "Credit Agreement").

      B.     On May 10, 2004 the Borrower acquired a 51% interest in an

approximately 29 mile flowline from MEGS, LLC an affiliate of Enron Corp. (such

acquisition, the "MEGS Acquisition") as more particularly described in that

certain Purchase and Sale Agreement dated as of April 28, 2004 by and among

MEGS, LLC, W & T Offshore, Inc. and the Borrower ("MEGS Acquisition Agreement").

      C.     On August 5, 2004 the Borrower acquired six offshore blocks in the

Gulf of Mexico from Juniper Energy L.P., an affiliate of Enron Corp. (such

acquisition, the "Juniper Acquisition") as more particularly described in that

certain Purchase and Sale Agreement dated as of August 5, 2004 by and between

Juniper Energy L.P. and the Borrower ("Juniper Acquisition Agreement").

      D.     At the request of the Borrower, the Administrative Agent and the

Lenders wish to, subject to the terms and conditions of this Agreement, provide

for a waiver of the Defaults and Events of Default (each as defined in the

Credit Agreement) existing as a result of the MEGS Acquisition and the Juniper

Acquisition (collectively, the "Acquisitions").

      E.     Furthermore, the Borrower wishes to create two new subsidiaries and

transfer certain assets described in Schedule A attached hereto (the "Texas

Assets") to one of such subsidiaries in the manner described in said Schedule A.

      F.     At the request of the Borrower, the Administrative Agent and the

Lenders wish to, subject to the terms and conditions of this Agreement, consent

to (i) the creation of such new subsidiaries, (ii) such transfer of the Texas

Assets and (iii) the amendment and restatement of the Borrower's bylaws in the

form attached as Exhibit A to this Agreement (the "Amended and Restated

Bylaws").

      THEREFORE, the Borrower, the Lenders, the Issuing Lender and the

Administrative Agent hereby agree as follows:

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                                    ARTICLE I.

                                   DEFINITIONS

      SECTION 1.01 TERMS DEFINED ABOVE. As used in this Agreement, each of the

terms defined in the opening paragraph and the Recitals above shall have the

meanings assigned to such terms therein.

      SECTION 1.02 TERMS DEFINED IN THE CREDIT AGREEMENT. Each term defined in

the Credit Agreement and used herein without definition shall have the meaning

assigned to such term in the Credit Agreement, unless expressly provided to the

contrary.

      SECTION 1.03 OTHER DEFINITIONAL PROVISIONS. The words "hereby", "herein",

"hereinafter", "hereof", "hereto" and "hereunder" when used in this Agreement

shall refer to this Agreement as a whole and not to any particular Article,

Section, subsection or provision of this Agreement. Article, Section, subsection

and Exhibit references herein are to such Articles, Sections, subsections and

Exhibits of this Agreement unless otherwise specified. All titles or headings to

Articles, Sections, subsections or other divisions of this Agreement or the

exhibits hereto, if any, are only for the convenience of the parties and shall

not be construed to have any effect or meaning with respect to the other content

of such Articles, Sections, subsections, other divisions or exhibits, such other

content being controlling as the agreement among the parties hereto. Whenever

the context requires, reference herein made to the single number shall be

understood to include the plural; and likewise, the plural shall be understood

to include the singular. Words denoting sex shall be construed to include the

masculine, feminine and neuter, when such construction is appropriate; and

specific enumeration shall not exclude the general but shall be construed as

cumulative. Definitions of terms defined in the singular or plural shall be

equally applicable to the plural or singular, as the case may be, unless

otherwise indicated.

                                   ARTICLE II.

                               WAIVER AND CONSENT

      SECTION 2.01 WAIVER. The Borrower hereby acknowledges the existence of the

following Defaults and Events of Default (collectively, the "Waiver Defaults"):

(a) the Borrower's violation of Section 6.22 of the Credit Agreement as a result

of the entering into the MEGS Acquisition Agreement and the consummation of the

MEGS Acquisition without the prior written consent of the Required Lenders, and

(b) the Borrower's violation of Section 6.22 of the Credit Agreement as a result

of the entering into the Juniper Acquisition Agreement and the consummation of

the Juniper Acquisition without the prior written consent of the Required

Lenders. Subject to the terms of this Agreement, the Lenders hereby waive the

Waiver Defaults.

      SECTION 2.02 CONSENTS. Subject to the terms of this Agreement, the Lenders

also hereby consent to (a) the Borrower creating a new wholly-owned subsidiary

that will be a Delaware limited liability company ("Delaware LLC"), (b) the

Borrower and such newly formed Delaware LLC creating a new subsidiary that will

be Delaware limited partnership ("Delaware LP") and of which the Delaware LLC

will hold the 99% limited partner interest and the Borrower will hold the 1%

general partner interest, (c) the transfer of the Texas Assets as

                                        2-

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detailed in Schedule A as contribution from the Borrower to the Delaware LP, (d)

the initial contribution of cash equity from the Borrower to the Delaware LLC,

and (e) the initial contribution of cash equity from the Delaware LLC to the

Delaware LP. The Administrative Agent hereby consents to the amendment to the

Borrower's bylaws as set forth in the Amended and Restated Bylaws. Each of the

Lenders hereby acknowledges and agrees to such consent by the Administrative

Agent. The consents by the Lenders and by the Administrative described in this

Section 2.02 are collectively referred to herein as the "Consents."

      SECTION 2.03 ACKNOWLEDGMENT AND AGREEMENT. The waiver and consents by the

Lenders described in the preceding Section 2.01 and 2.02 are contingent upon the

satisfaction of the conditions precedent set forth below and are strictly

limited to the Waiver Defaults and the Consents to the extent described herein.

Nothing contained herein shall be construed to be a consent to or a permanent

waiver of the Sections covered by the Waiver Defaults or the Consents or any

other terms, provisions, covenants, warranties or agreements contained in the

Credit Agreement or in any of the other Loan Documents. The Lenders reserve the

right to exercise any rights and remedies available to them in connection with

any other present or future defaults with respect to the Credit Agreement or any

other provision of any Loan Document. The descriptions herein of the Waiver

Defaults and the Consents are based upon the information provided to the Lenders

on or prior to the date hereof and shall not be deemed to exclude the existence

of any other Defaults or Events of Default. The failure of the Lenders to give

notice to the Borrower or the Guarantors of any such other Defaults or Events of

Default is not intended to be nor shall be a waiver thereof. The Borrower hereby

agrees and acknowledges that the Lenders require and will require strict

performance by the Borrower of all of its obligations, agreements and covenants

contained in the Credit Agreement and the other Loan Documents, and no inaction

or action regarding any Default or Event of Default is intended to be or shall

be a waiver thereof.

                                  ARTICLE III.

                         REPRESENTATIONS AND WARRANTIES

      The Borrower represents and warrants that: (a) the representations and

warranties contained in Article IV of the Credit Agreement and the

representations and warranties contained in the Security Instruments, the

Guaranties, and each of the other Loan Documents are true and correct in all

material respects on and as of the Effective Date, before and after giving

effect to the Acquisitions and after giving effect to the terms of this

Agreement, as though made on and as of such date, except those representations

and warrantie