Filed by 3TEC Energy Corporation Pursuant to Rule 425 of the Securities

Act of 1933 and deemed filed pursuant to Rule 14a-12 of the

Securities Exchange Act of 1934

Subject Company: 3TEC Energy Corporation

Registration Statement No.: 333-103149

PXP

Plains Exploration & Production Company

Investor Presentations

Boston, MA & New York, NY

May 19-21, 2003

Forward Looking Statements and Additional Information

Except for the historical information contained herein, the matters discussed in this presentation are forward-looking statements that involve certain risks and uncertainties that could cause actual results to differ materially. These risks and uncertainties include, among other things, economic conditions, oil and gas price volatility, the success of risk management activities, uncertainties inherent in the the exploration for and development and production of oil and gas and in estimating reserves, regulatory changes and other factors discussed in PXP’s filings with the Securities and Exchange Commission.

Investors and security holders are urged to read the proxy statement/prospectus that will be included in the Registration Statement on Form S-4 to be filed with the SEC in connection with the proposed merger. PXP and 3TEC will file the proxy statement/prospectus with the SEC. Investors and security holders may obtain a free copy of the proxy statement/prospectus (when available) and other documents filed by PXP and 3TEC with the SEC at the SEC’s web site at www.sec.gov. The proxy statement/prospectus and such other documents (relating to PXP) may also be obtained for free from PXP by directing such request to: Plains Exploration & Production Company, 500 Dallas, Suite 700 Houston, TX 77002, Attention: Joanna Pankey; telephone: (713) 739-6700; e-mail: jpankey@plainsxp.com. The proxy statement/prospectus and such other documents (relating to 3TEC) may also be obtained for free from 3TEC by directing such request to: 3TEC Energy Corporation, 700 Milam, Suite 1100, Houston, Texas 77002.

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 merger. Information regarding such persons and a description of their interests in the merger will be contained in the Registration Statement on Form S-4 when it is filed.

3TEC, its directors, executive officers and certain members of management and employees may be considered “participants in the solicitation” in connection with the merger. Information regarding such persons and a description of their interests in the merger will be contained in the Registration Statement on Form S-4 when it is filed.

PXP 2

Participants

Jim Flores

Chairman & CEO

John Raymond

President & COO

Stephen Thorington

Executive Vice President & CFO

Winston Talbert

Vice President – Finance & Investor Relations

PXP 3

3Tec Transaction Overview

Pro Forma Operating Areas

[GRAPHIC]

PXP 5

Pro Forma – Reserves & Production

Reserves	Production
Gas 19%	Gas 37%
Oil 81%	Oil 63%

302 MMBOE Reserves total (12/31/02)

20+ Total proved R/P

58% Proved Developed Reserves (12-year R/P)

PXP 6

PXP Pro Forma Operational Strategy

	Target % of Budget
¨ Development:    East Texas Gas & California Onshore Oil	50%
¨ Exploitation:    South Louisiana Gas & Inglewood Deep Oil	35%
¨ Exploration:    South Louisiana Gas & Rocky Point Oil	15%

PXP 7

Operational Strategy Detail

PXP 8

Development Areas

Development

[GRAPHIC]

PXP 9

Development Inventory

	2003	2004	2005	2006	2007	Total
Inglewood	24	28	38	38	32	160
Montebello	—	10	23	11	11	55
Arroyo Grande	18	40	40	40	40	178
Mount Poso	97	100	—	—	—	197
Illinois	43	42	39	34	34	192
East Texas	36	31	31	28	—	126
So. TX, OK. Other	14	8	—	—	—	22
Total	232	259	171	151	117	930

PXP 10

Inglewood Field Structural Setting

[GRAPHIC]

PXP 11

East Texas – Glenwood/White Oak Field

[GRAPHIC]

PXP 12

Pro Forma Activity Areas

Exploitation

[GRAPHIC]

PXP 13

Exploitation Inventory

Field	County / Parish	Operator	Prospects	Average NRI		Unrisked Net MMBOE
Inglewood Deep	Los Angeles	Plains E&P	100+	85	%	87.0
Breton Sound	Plaquemines	3TEC/Century	14	39	%	14.8
Garden City	St. Mary	3TEC	3	35	%	5.2
Others	LA/TX/OK	3TEC, Others	15	35	%	2.9
Total Prospects			130+			109.9

PXP 14

Inglewood Deep

Inglewood Field – Shallow and Deep Reservoirs

	Vickers/Rindge (Proven Reserves)
[GRAPHICS]
	Various Deep Zones (Potential Reserves)

PXP 15

Inglewood Deep Development Sentous Reservoir

[GRAPHIC]

PXP 16

Breton Sound Area

[GRAPHIC]

PXP 17

Garden City Area

[GRAPHIC]

PXP 18

Pro Forma Activity Areas

Exploration

[GRAPHIC]

Production/Development

Exploitation

Exploration

PXP 19

Bayou Carlin 3-D Exploration Area

[GRAPHIC]

PXP 20

Point Arguello Area – Rocky Point Prospect

	RP Test Wells
	1. 1,629 BOPD
[GRAPHIC]	2. 3,500 BOPD
	3. 1,100 BOPD

PXP 21

Inventory Summary

	Area	Drills		Oil / Gas
Development	California	800		Oil
	East Texas	125		Gas
Exploitation	Inglewood Deep	100	+	Oil
	Breton Sound	12		Gas
	Garden City	3		Gas
Exploratory	Rocky Point	8		Oil
	Bayou Carlin	2		Gas
	Bay de Chene	2		Gas
	Deep Planulina	1		Gas

PXP 22

PXP Financial Overview

Financing Strategy

¨ Maintain well-capitalized, liquid balance sheet

– BB-/Ba3 stable outlook senior implied rating; B2/B stable outlook senior subordinated rating

– Improving coverage ratios

¨ Apply free cash flow to reduce bank debt

¨ 2004 target mid 40% debt/total capital ratio

¨ Continue hedging program to manage commodity risk

PXP 24

Pro Forma Capitalization

	As of 3/31/03
	PXP Actual		Adjustments		Pro Forma
($ in millions)
Cash and cash equivalents	$	1.0	$	1.8	$	2.8
Total Debt (Including Current Maturities):
Bank Debt / Credit Facility	$	32.5	$	218.8	$	251.3
8.75% Senior Subordinated Notes		200.0		75.0		275.0
Other		1.0		—		1.0
TOTAL DEBT	$	233.5	$	293.8	$	527.3
Common Shareholders’ Equity		192.9		150.9		343.8
TOTAL BOOK CAPITALIZATION	$	426.4	$	444.7	$	871.1

PXP 25

Pro Forma Financial Highlights

($ in thousands, except per unit amounts)
	PXP & 3TEC Pro Forma 3/31/03		Per BOE
Total Production (MBOE)		3,553
Average Daily Production (MBOE/Day)		39.5
NYMEX Oil Price:	$	33.80
NYMEX Gas Price:	$	6.59
Oil Revenue		53,875	$	22.57
Gas Revenue		31,591	$	4.52
LOE		24,133	$	6.79
Production Taxes		3,770	$	1.06
Gathering Expense		1,106	$	0.31
G&A Expense		5,385	$	1.52
Interest Expense		7,145	$	2.01
Net income		17,241
Earnings Per Share-  (Diluted)	$	0.43
Discretionary Cash Flow Per Share	$	0.99
EBITDA	$	50,685
Discretionary Cash Flow	$	39,600
Oil & Gas Capital Expenditures	$	37,052
Free Cash Flow	$	2,548

PXP 26

Historical and Pro Forma Balance Sheets

( $ in thousands )
	PXP-Alone 2002 Historical	PXP & 3TEC Pro Forma 3/31/03
Total Current Assets	38,739	69,254
Property and equipment, net	493,212	953,218
Other assets	18,929	137,877
	550,880	1,160,349
Total Current Liabilities	86,175	110,263
Total Long-Term Debt	233,166	527,284
Deferred Income Tax	51,416	138,513
Other Long-Term Liabilities	6,303	40,539
Total Stockholders’ Equity	173,820	343,750
	550,880	1,160,349

PXP 27

PXP Current Pro Forma Hedge Positions

Production Period	Instrument Type	Daily Volumes	Average Price
2003
Crude Oil	Swap	20,250 bopd	$24.09
Natural Gas	Swap	50 mmcf/d	$5.00
2003
Crude Oil	Swap	18,500 bopd	$23.85
Natural Gas	Swap	20 mmcf/d	$4.45
Natural Gas	Collar	20 mmcf/d	$4.00-$5.00
2003
Crude Oil	Swap	5,000 bopd	$23.57

PXP 28

2003 Outlook

	Pro Forma Combined Full Year 2003
Production:
MBOE per day	39.4-41.0
% Oil	67	%
% Gas	33	%
Differential to NYMEX (pre-hedge) Oil ($ per bbl)	$4.00-$ 4.35
Operating Cost per BOE:
Production Expense	$6.85-$ 7.00
Production and ad valorem taxes	$1.15-$ 1.20
General & Administrative	$1.40-$ 1.50
Expected Capital Expenditure (millions)	$ 115-$  135

PXP 29

PXP Summary

Strategic Focus

¨ Manage costs to increase operating margins

¨ Exploit opportunities related to current infrastructure

– Deep Inglewood

– Rocky Point

– East Texas

¨ Exploit 3Tec and PXP portfolio to maximize returns on capital

¨ Reduce debt in robust commodity price environment

¨ Pursue organic and external growth opportunities

PXP 31

PXP Reconciliation of Non-GAAP Financial Measures

1^st Quarter Results Pro Forma for 3TEC Merger and $75MM Senior Subordinated Debt Offering

($ in thousands)
	1st Qtr.—2003
Income before cumulative effect of accounting change		17,241
Interest expense		7,145
Income tax expense		11,494
Depreciation, depletion and amortization		14,805
EBITDA	$	50,685
Reconciliation Of EBITDA To Net Cash Provided By Operating Activities
Net cash provided by operating activities		28,663
Interest expense		7,145
Current tax expense		2,299
Other noncash items		1,443
Change in assets and liabilities from operating activities		11,135
EBITDA	$	50,685
Reconciliation Of Discretionary Cash Flow To Net Cash Provided By Operating Activities
Net cash provided by operating activities		28,663
Change in assets and liabilities from operating activities		11,135
Other		(198	)
Discretionary cash flow	$	39,600
Discretionary cash flow		39,600
Capital costs incurred		37,052
Free cash flow	$	2,548

PXP 32

PXP

Plains Exploration & Production Company

Investor Presentations

Boston, MA & New York, NY

May 19-21, 2003

33

On February 12, 2003, PXP and 3TEC filed a joint proxy statement/prospectus with the Securities and Exchange Commission. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS BECAUSE IT CONTAINS IMPORTANT INFORMATION ABOUT PXP AND 3TEC AND THE PROPOSED TRANSACTION. The proxy statement/prospectus was sent to security holders of PXP and 3TEC on May 5, 2003. Investors and security holders may obtain a free copy of the proxy statement/prospectus and other documents filed by PXP and 3TEC with the SEC at the SEC’s web site at www.sec.gov. The proxy statement/prospectus and such other documents (relating to PXP) may also be obtained for free from PXP by directing such request to: Plains Exploration & Production Company, 500 Dallas, Suite 700 Houston, Tx 77002, Attention: Joanna Pankey; telephone: (713) 739-6700; e-mail: jpankey@plainsxp.com. The proxy statement/prospectus and such other documents (relating to 3TEC) may also be obtained for free from 3TEC by directing such request to: 3TEC Energy Corporation, 700 Milam, Suite 1100, Houston, Texas 77002, Attention: Investor Relations; telephone: (713) 821-7100.

PXP and 3TEC and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of PXP and 3TEC in connection with the merger. Information regarding the persons who may, under SEC rules, be considered to be participants in the solicitation of PXP’s and 3TEC’s stockholders is set forth in the joint proxy statement / prospectus that forms a part of the Registration Statement on Form S-4, as amended, that PXP filed on May 1, 2003.

34