SC 13G

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934
(Amendment No. )*

Plains Exploration & Production Company

(Name of Issuer)

Common Stock, par value $0.01

(Title of Class of Securities)

726505100

(CUSIP Number)

October 10, 2007

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

     o Rule 13d-1(b)

     þ Rule 13d-1(c)

     o Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 726505100 

1	NAMES OF REPORTING PERSONS: Fir Tree Value Master Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   o
	(b)   o
3	SEC USE ONLY:
4	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Cayman Islands
		5	SOLE VOTING POWER:
NUMBER OF			0
SHARES		6	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			5,535,683
EACH		7	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			0
WITH:		8	SHARED DISPOSITIVE POWER:
			5,535,683
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	5,535,683
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9):
	7.6%
12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO

THE SHARES REFERRED TO ON THIS SCHEDULE 13G WERE PREVIOUSLY REPORTED BY THE REPORTING PERSON ON SCHEDULE 13D, AS AMENDED. PURSUANT TO SECTION 240.13D-1(C), AS OF THE REPORTING DATE, THE REPORTING PERSON IS ELIGIBLE TO REPORT THE SHARES BENEFICIALLY OWNED BY THE REPORTING PERSON ON SCHEDULE 13G.

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CUSIP No. 726505100 

1	NAMES OF REPORTING PERSONS: Fir Tree Recovery Master Fund, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   o
	(b)   o
3	SEC USE ONLY:
4	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Cayman Islands
		5	SOLE VOTING POWER:
NUMBER OF			0
SHARES		6	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			1,159,617
EACH		7	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			0
WITH:		8	SHARED DISPOSITIVE POWER:
			1,159,617
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	1,159,617
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9):
	1.6%
12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	PN

THE SHARES REFERRED TO ON THIS SCHEDULE 13G WERE PREVIOUSLY REPORTED BY THE REPORTING PERSON ON SCHEDULE 13D, AS AMENDED. PURSUANT TO SECTION 240.13D-1(C), AS OF THE REPORTING DATE, THE REPORTING PERSON IS ELIGIBLE TO REPORT THE SHARES BENEFICIALLY OWNED BY THE REPORTING PERSON ON SCHEDULE 13G.

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CUSIP No. 726505100 

1	NAMES OF REPORTING PERSONS: Fir Tree, Inc.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   o
	(b)   o
3	SEC USE ONLY:
4	CITIZENSHIP OR PLACE OF ORGANIZATION:
	New York
		5	SOLE VOTING POWER:
NUMBER OF			0
SHARES		6	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			6,695,300
EACH		7	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			0
WITH:		8	SHARED DISPOSITIVE POWER:
			6,695,300
9	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	6,695,300
10	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
11	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9):
	9.2%
12	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO

THE SHARES REFERRED TO ON THIS SCHEDULE 13G WERE PREVIOUSLY REPORTED BY THE REPORTING PERSON ON SCHEDULE 13D, AS AMENDED. PURSUANT TO SECTION 240.13D-1(C), AS OF THE REPORTING DATE, THE REPORTING PERSON IS ELIGIBLE TO REPORT THE SHARES BENEFICIALLY OWNED BY THE REPORTING PERSON ON SCHEDULE 13G.

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SCHEDULE 13G

This Schedule 13G (the “Schedule 13G”) is being filed on behalf of Fir Tree Value Master Fund, L.P., a Cayman Islands exempted limited partnership (“Fir Tree Value”), Fir Tree Recovery Master Fund, L.P., a Cayman Islands exempted limited partnership (“Fir Tree Recovery”) and Fir Tree, Inc., a New York corporation (“Fir Tree”), relating to common stock, par value $0.01 (the “Common Stock”) of Plains Exploration & Production Company, a Delaware corporation (the “Issuer”), purchased by Fir Tree Value and Fir Tree Recovery. Fir Tree is the investment manager of both Fir Tree Value and Fir Tree Recovery.

Item 1 (a)	Name of Issuer.
	Plains Exploration & Production Company
Item 1 (b)	Address of Issuer’s Principal Executive Offices.
	700 Milam Street, Suite 3100 Houston, Texas 77002
Item 2 (a)	Name of Person Filing.
Item 2 (b)	Address of Principal Business Office.
Item 2 (c)	Place of Organization.
	Fir Tree, Inc. 505 Fifth Avenue 23rd Floor New York, New York 10017 A New York corporation
	Fir Tree Value Master Fund, L.P. c/o Admiral Administration Ltd. Admiral Financial Center, 5th Floor 90 Fort Street, Box 32021 SMB Grand Cayman, Cayman Islands A Cayman Islands exempted limited partnership
	Fir Tree Recovery Master Fund, L.P. c/o Admiral Administration Ltd. Admiral Financial Center, 5th Floor 90 Fort Street, Box 32021 SMB Grand Cayman, Cayman Islands A Cayman Islands exempted limited partnership

Fir Tree, Inc. is the investment manager for each of Fir Tree Value and Fir Tree Recovery and has been granted investment discretion over portfolio investments, including the Common Stock (as defined below), held by each of them.

Item 2 (d)	Title of Class of Securities.
	Common stock, par value $0.01 (the “Common Stock”).

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Item 2 (e)	CUSIP Number.
	726505100
Item 3	Reporting Person.
	The person filing is not listed in Items 3(a) through 3(j).
Item 4	Ownership.

(a)	Fir Tree Value and Fir Tree Recovery are the beneficial owners of 5,535,683 shares of Common Stock and 1,159,617 shares of Common Stock, respectively (which includes the shares underlying American-style call options exercisable through dates ranging from October 19, 2007 to February 15, 2008). Fir Tree may be deemed to beneficially own the shares of Common Stock held by Fir Tree Value and Fir Tree Recovery as a result of being the investment manager of Fir Tree Value and Fir Tree Recovery.
(b)	Fir Tree Value and Fir Tree Recovery are the beneficial owners of 7.6% and 1.6%, respectively, of the outstanding shares of Common Stock. Collectively, the Reporting Persons beneficially own 6,695,300 shares of Common Stock which represent 9.2% of the shares of Common Stock outstanding. These percentages are determined by dividing the number of shares of Common Stock beneficially held by 72,766,033, the number of shares of Common Stock issued and outstanding as of September 25, 2007 according to the Issuer’s Proxy Statement/Prospectus filed with the Securities and Exchange Commission on October 1, 2007.
(c)	Fir Tree Value may direct the vote and disposition of 5,535,683 shares of Common Stock. Fir Tree Recovery may direct the vote and disposition of 1,159,617 shares of Common Stock. Fir Tree has been granted investment discretion over the Common Stock held by Fir Tree Value and Fir Tree Recovery.

Item 5	Ownership of Five Percent or Less of a Class.
	Inapplicable.
Item 6	Ownership of More Than Five Percent on Behalf of Another Person.
	Inapplicable.
Item 7	Identification and Classification of the Subsidiary which Acquired the Security Being Reported On by the Parent Holding Company.
	Inapplicable.
Item 8	Identification and Classification of Members of the Group.
	Inapplicable.
Item 9	Notice of Dissolution of Group.
	Inapplicable.
Item 10	Certification.
	By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

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Exhibits
Exhibit 1	Press Release dated October 9, 2007.
Exhibit 2	Joint Filing Agreement dated as of August 17, 2007 among Fir Tree Value Master Fund, L.P., Fir Tree Recovery Master Fund, L.P. and Fir Tree, Inc.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: October 10, 2007

FIR TREE VALUE MASTER FUND, L.P.
By:	FIR TREE, INC., its Manager
	By:	/s/ Jeffrey Tannenbaum
		Name:  Jeffrey Tannenbaum
		Title:  President
FIR TREE RECOVERY MASTER FUND, L.P.
By:	FIR TREE, INC., its Manager
	By:	/s/ Jeffrey Tannenbaum
		Name:  Jeffrey Tannenbaum
		Title:  President
FIR TREE, INC.
By:	/s/ Jeffrey Tannenbaum
	Name:	Jeffrey Tannenbaum
	Title:	President

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EX-99.1

EXHIBIT 1

NEWS RELEASE

FOR IMMEDIATE RELEASE

FIR TREE ANNOUNCES SUPPORT FOR POGO ACQUISITION

Houston, Texas and New York, New York, October 9, 2007—Plains Exploration & Production Company (NYSE: PXP) and Fir Tree Partners today jointly announced that Fir Tree has agreed to support PXP’s proposed acquisition of Pogo Producing Company (NYSE: PPP).

Fir Tree Partners will vote its shares in support of the acquisition proposal based on PXP’s continued commitment to implement, following the acquisition, its proven asset rationalization program combined with an ongoing significant share repurchase program and evaluate the necessary steps to achieve MLP valuations by forming a master limited partnership or using the MLP market to unlock value for shareholders.

Andrew Fredman of Fir Tree Partners said, “After a number of constructive conversations, we are pleased to have come to an amicable resolution regarding the Pogo acquisition and look forward to Plains Exploration’s implementation of these post-acquisition measures. We believe these measures are the most effective steps to creating value for shareholders. In light of Plains Exploration’s commitments, we are happy to support the Pogo acquisition and plan to vote our shares in favor of it. Jim Flores and his management team have demonstrated a superb long-term record of value creation and we believe that the articulated strategy will help ensure that their superior record continues forward.”

James Flores of Plains Exploration said, “We appreciate Fir Tree’s support of the Pogo acquisition, which will enable PXP to continue its stated course of action of increasing shareholder value.”

PXP is an independent oil and gas company primarily engaged in the upstream activities of acquiring, developing, exploiting, exploring and producing oil and gas in its core areas of operation: onshore and offshore California, Colorado, and the Gulf Coast region of the United States. PXP is headquartered in Houston, Texas.

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ADDITIONAL INFORMATION & FORWARD LOOKING STATEMENTS

This press release contains forward-looking information regarding PXP that is intended to be covered by the safe harbor “forward-looking statements” provided by the Private Securities Litigation Reform Act of 1995. All statements included in this press release that address activities, events or developments that PXP expects, believes or anticipates will or may occur in the future are forward-looking statements. These include statements regarding:

*	completion of the proposed merger,
*	effective integration of the two companies,
*	reserve and production estimates,
*	oil and gas prices,
*	the impact of derivative positions,
*	production expense estimates,
*	cash flow estimates,
*	future financial performance,
*	planned capital expenditures, and
*	other matters that are discussed in PXP’s filings with the SEC.

These statements are based on our current expectations and projections about future events and involve known and unknown risks, uncertainties, and other factors that may cause our actual results and performance to be materially different from any future results or performance expressed or implied by these forward-looking statements. Please refer to our filings with the SEC, including our Form 10-K for the year ended December 31, 2006, for a discussion of these risks.

All forward-looking statements in this report are made as of the date hereof, and you should not place undue reliance on these statements without also considering the risks and uncertainties associated with these statements and our business that are discussed in this report and our other filings with the SEC. Moreover, although we believe the expectations reflected in the forward-looking statements are based upon reasonable assumptions, we can give no assurance that we will attain these expectations or that any deviations will not be material. Except for any obligation to disclose material information under the Federal securities laws, we do not intend to update these forward-looking statements and information.

PXP AND POGO HAVE FILED A JOINT PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS WITH THE SECURITIES AND EXCHANGE COMMISSION. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ CAREFULLY THE DEFINITIVE JOINT PROXY STATEMENT/PROSPECTUS BECAUSE IT CONTAINS IMPORTANT INFORMATION REGARDING PXP, POGO AND THE ACQUISITION. A DEFINITIVE JOINT PROXY STATEMENT/PROSPECTUS IS BEING SENT TO SECURITY HOLDERS OF PXP SEEKING THEIR APPROVAL OF THE ISSUANCE OF SHARES OF PXP STOCK TO BE USED AS MERGER CONSIDERATION AND SECURITY HOLDERS OF POGO SEEKING THEIR APPROVAL OF THE ACQUISITION. INVESTORS AND SECURITY HOLDERS MAY OBTAIN A FREE COPY OF THE DEFINITIVE JOINT

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PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS FILED BY PXP AND POGO WITH THE SEC AT THE SEC’S WEBSITE AT http://WWW.SEC.GOV.

THE DEFINITIVE JOINT PROXY STATEMENT/PROSPECTUS AND SUCH OTHER DOCUMENTS (RELATING TO PXP) MAY ALSO BE OBTAINED FOR FREE FROM PXP BY DIRECTING A REQUEST TO PLAINS EXPLORATION & PRODUCTION COMPANY, 700 MILAM, SUITE 3100, HOUSTON, TX 77002, ATTENTION: JOANNA PANKEY; TELEPHONE: (713) 579-6000, E-MAIL: JPANKEY@PXP.COM.

THE DEFINITIVE JOINT PROXY STATEMENT/PROSPECTUS AND SUCH OTHER DOCUMENTS (RELATING TO POGO) MAY ALSO BE OBTAINED FOR FREE FROM POGO BY DIRECTING A REQUEST TO POGO PRODUCING COMPANY, 5 GREENWAY PLAZA, SUITE 2700, HOUSTON, TX 77046, ATTENTION: CLAY JEANSONNE, TELEPHONE: (713) 297-5000, E-MAIL: JEANSONC@POGOPRODUCING.COM.

PXP, its directors, executive officers and certain members of management and employees may be considered “participants in the solicitation” of proxies from PXP’s stockholders in connection with the acquisition. Information regarding such persons and a description of their interest in the acquisition is contained in the joint proxy statement/prospectus on file with the SEC. Information concerning beneficial ownership of PXP stock by its directors and certain executive officers is included in its proxy statement dated March 29, 2007 and subsequent statements of changes in beneficial ownership on file with the SEC.

Pogo, its directors, executive officers and certain members of management and employees may be considered “participants in the solicitation” of proxies from Pogo’s stockholders in connection with the acquisition. Information regarding such persons and a description of their interest in the acquisition is contained in the joint proxy statement/prospectus on file with the SEC. Information concerning beneficial ownership of Pogo stock by its directors and certain executive officers is included in its proxy statement dated April 20, 2007 and subsequent statements of changes in beneficial ownership on file with the SEC.

SOURCE: Plains Exploration & Production Company, Fir Tree Partners

CONTACT:

Scott Winters, Vice President—Investor Relations of Plains Exploration & Production Company, 713-579-6190, or 1-800-934-6083

Clinton Biondo of Fir Tree Partners, 305-704-5778

EX-99.2

EXHIBIT 2

JOINT FILING AGREEMENT

     In accordance with Rule 13d-l(k) under the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing on behalf of each of them of a Statement on Schedule 13G (including any and all amendments thereto) with respect to the shares of Common Stock of Plains Exploration & Production Company, a Delaware corporation, and further agree that this Joint Filing Agreement shall be included as an Exhibit to such joint filings.

     The undersigned further agree that each party hereto is responsible for the timely filing of such Statement on Schedule 13G and any amendments thereto, and for the accuracy and completeness of the information concerning such party contained therein; provided, however, that no party is responsible for the accuracy or completeness of the information concerning any other party, unless such party knows or has reason to believe that such information is inaccurate.

     This Joint Filing Agreement may be signed in counterparts with the same effect as if the signature on each counterpart were upon the same instrument.

     IN WITNESS WHEREOF, the undersigned have executed this Agreement as of August 17, 2007.

FIR TREE VALUE MASTER FUND, L.P. By: FIR TREE, INC., its Manager
	By:	/s/ Jeffrey Tannenbaum
		Name:	Jeffrey Tannenbaum
		Title:	President
FIR TREE RECOVERY MASTER FUND, L.P. By: FIR TREE, INC., its Manager
	By:	/s/ Jeffrey Tannenbaum
		Name:	Jeffrey Tannenbaum
		Title:	President
FIR TREE, INC.
By:	/s/ Jeffrey Tannenbaum
		Name:	Jeffrey Tannenbaum
		Title:	President