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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13D
             INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
     TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a)

                                (AMENDMENT NO. 1)


                              PLAINS RESOURCES INC.
                                (Name of Issuer)


COMMON STOCK, PAR VALUE $.10 PER SHARE                        726540503
--------------------------------------------------------------------------------
   (Title of class of securities)                           (CUSIP number)


JOSEPH A. ORLANDO                       WILLIAM ACKMAN
LEUCADIA NATIONAL CORPORATION           PERSHING SQUARE CAPITAL MANAGEMENT, LLC
315 PARK AVENUE SOUTH                   110 EAST 42ND STREET
NEW YORK, NEW YORK 10010                NEW YORK, NEW YORK  10017
(212) 460-1900                          (212) 813-3700
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                  (Name, address and telephone number of person
                authorized to receive notices and communications)


                                  MARCH 5, 2004
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             (Date of event which requires filing of this statement)


If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rules 13d-1(e), 13d-1(f) or 13d-1(g), check the following
box [_].


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-----------------------------------------------------------------                ------------------------------------------------
CUSIP No. 726540503                                                    13D                                        Page 2
-----------------------------------------------------------------                ------------------------------------------------
               
----------------- ----------------------------------------------- ---------------------------------------------------------------
       1          NAME OF REPORTING PERSON:                       Leucadia National Corporation
                  I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):
----------------- ---------------------------------------------------------------------------------------------------------------
       2          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                                (A) [X]
                                                                                                                   (B) [_]
----------------- ---------------------------------------------------------------------------------------------------------------
       3          SEC USE ONLY

----------------- -------------------------- ------------------------------------------------------------------------------------
       4          SOURCE OF FUNDS:           NA

----------------- ---------------------------------------------------------------------------------------------------------------
       5          CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):             [_]
----------------- -------------------------------------------------------------- ------------------------------------------------
       6          CITIZENSHIP OR PLACE OF ORGANIZATION:                          New York

--------------------------- ------ --------------------------------------------- ------------------------------------------------
        NUMBER OF             7    SOLE VOTING POWER:                            0
          SHARES
                            ------ --------------------------------------------- ------------------------------------------------
       BENEFICIALLY           8    SHARED VOTING POWER:                          0
         OWNED BY
                            ------ --------------------------------------------- ------------------------------------------------
           EACH               9    SOLE DISPOSITIVE POWER:                       0
        REPORTING
                            ------ --------------------------------------------- ------------------------------------------------
       PERSON WITH           10    SHARED DISPOSITIVE POWER:                     0

----------------- ---------------------------------------------------------------------------------------------------------------
       11         AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:   0

----------------- ---------------------------------------------------------------------------------------------------------------
       12         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                            [_]

----------------- ---------------------------------------------------------------------------------------------------------------
       13         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):   0%

----------------- ----------------------------------------------- ---------------------------------------------------------------
       14         TYPE OF REPORTING PERSON:                       CO

----------------- ----------------------------------------------- ---------------------------------------------------------------





                                       2

-----------------------------------------------------------------                ------------------------------------------------
CUSIP No. 726540503                                                    13D                                        Page 3
-----------------------------------------------------------------                ------------------------------------------------

----------------- ----------------------------------------------- ---------------------------------------------------------------
       1          NAME OF REPORTING PERSON:                       Pershing Square, L.P.
                  I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):   38-3694138
----------------- ---------------------------------------------------------------------------------------------------------------
       2          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                               (A) [X]
                                                                                                                  (B) [_]
----------------- ---------------------------------------------------------------------------------------------------------------
       3          SEC USE ONLY

----------------- -------------------------- ------------------------------------------------------------------------------------
       4          SOURCE OF FUNDS:           NA

----------------- ---------------------------------------------------------------------------------------------------------------
       5          CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):             [_]
----------------- -------------------------------------------------------------- ------------------------------------------------
       6          CITIZENSHIP OR PLACE OF ORGANIZATION:                          Delaware

--------------------------- ------ --------------------------------------------- ------------------------------------------------
        NUMBER OF             7    SOLE VOTING POWER:                            0
          SHARES
                            ------ --------------------------------------------- ------------------------------------------------
       BENEFICIALLY           8    SHARED VOTING POWER:                          1,258,500
         OWNED BY
                            ------ --------------------------------------------- ------------------------------------------------
           EACH               9    SOLE DISPOSITIVE POWER:                       0
        REPORTING
                            ------ --------------------------------------------- ------------------------------------------------
       PERSON WITH           10    SHARED DISPOSITIVE POWER:                     1,258,500

----------------- ---------------------------------------------------------------------------------------------------------------
       11         AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:   1,258,500

----------------- ---------------------------------------------------------------------------------------------------------------
       12         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                              [_]

----------------- ---------------------------------------------------------------------------------------------------------------
       13         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):   5.33%

----------------- ----------------------------------------------- ---------------------------------------------------------------
       14         TYPE OF REPORTING PERSON:                       PN

----------------- ----------------------------------------------- ---------------------------------------------------------------





                                       3

-----------------------------------------------------------------                ------------------------------------------------
CUSIP No. 726540503                                                    13D                                        Page 4
-----------------------------------------------------------------                ------------------------------------------------

----------------- ----------------------------------------------- ---------------------------------------------------------------
       1          NAME OF REPORTING PERSON:                                  Pershing Square GP, LLC
                  I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):   38-3694141
----------------- ---------------------------------------------------------------------------------------------------------------
       2          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                                (A) [X]
                                                                                                                   (B) [_]
----------------- ---------------------------------------------------------------------------------------------------------------
       3          SEC USE ONLY

----------------- -------------------------- ------------------------------------------------------------------------------------
       4          SOURCE OF FUNDS:           N/A

----------------- ---------------------------------------------------------------------------------------------------------------
       5          CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):            [_]
----------------- -------------------------------------------------------------- ------------------------------------------------
       6          CITIZENSHIP OR PLACE OF ORGANIZATION:                          Delaware

--------------------------- ------ --------------------------------------------- ------------------------------------------------
        NUMBER OF             7    SOLE VOTING POWER:                            0
          SHARES
                            ------ --------------------------------------------- ------------------------------------------------
       BENEFICIALLY           8    SHARED VOTING POWER:                          1,258,500
         OWNED BY
                            ------ --------------------------------------------- ------------------------------------------------
           EACH               9    SOLE DISPOSITIVE POWER:                       0
        REPORTING
                            ------ --------------------------------------------- ------------------------------------------------
       PERSON WITH           10    SHARED DISPOSITIVE POWER:                     1,258,500

----------------- ---------------------------------------------------------------------------------------------------------------
       11         AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:   1,258,500
----------------- ---------------------------------------------------------------------------------------------------------------
       12         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                             [_]

----------------- ---------------------------------------------------------------------------------------------------------------
       13         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):   5.33%

----------------- ----------------------------------------------- ---------------------------------------------------------------
       14         TYPE OF REPORTING PERSON:                       OO

----------------- ----------------------------------------------- ---------------------------------------------------------------





                                       4

-----------------------------------------------------------------                ------------------------------------------------
CUSIP No. 726540503                                                    13D                                        Page 5
-----------------------------------------------------------------                ------------------------------------------------

----------------- ----------------------------------------------- ---------------------------------------------------------------
       1          NAME OF REPORTING PERSON:                                  William Ackman
                  I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):
----------------- ---------------------------------------------------------------------------------------------------------------
       2          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                                              (A) [X]
                                                                                                                 (B) [_]
----------------- ---------------------------------------------------------------------------------------------------------------
       3          SEC USE ONLY

----------------- -------------------------- ------------------------------------------------------------------------------------
       4          SOURCE OF FUNDS:           N/A

----------------- ---------------------------------------------------------------------------------------------------------------
       5          CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e):           [_]
----------------- -------------------------------------------------------------- ------------------------------------------------
       6          CITIZENSHIP OR PLACE OF ORGANIZATION:                          United States

--------------------------- ------ --------------------------------------------- ------------------------------------------------
        NUMBER OF             7    SOLE VOTING POWER:                            0
          SHARES
                            ------ --------------------------------------------- ------------------------------------------------
       BENEFICIALLY           8    SHARED VOTING POWER:                          1,258,500
         OWNED BY
                            ------ --------------------------------------------- ------------------------------------------------
           EACH               9    SOLE DISPOSITIVE POWER:                       0
        REPORTING
                            ------ --------------------------------------------- ------------------------------------------------
       PERSON WITH           10    SHARED DISPOSITIVE POWER:                     1,258,500

----------------- ---------------------------------------------------------------------------------------------------------------
       11         AGGREGATE AMOUNT BENEFICIALLY OWNED BY REPORTING PERSON:   1,258,500

----------------- ---------------------------------------------------------------------------------------------------------------
       12         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES:                             [_]

----------------- ---------------------------------------------------------------------------------------------------------------
       13         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):   5.33%

----------------- ----------------------------------------------- ---------------------------------------------------------------
       14         TYPE OF REPORTING PERSON:                       IN

----------------- ----------------------------------------------- ---------------------------------------------------------------




                                       5

           This Amendment No. 1, amends the Schedule 13D filed on February 23,
2004, and is filed by Leucadia National Corporation ("Leucadia"), Pershing
Square, L.P., Pershing Square GP, LLC and William Ackman (collectively, the
"Reporting Persons") with respect to the common stock, par value $0.10 per share
("Common Stock"), of Plains Resources Inc. (the "Company").

Item 4.    Purpose of Transaction.

           Item 4 is hereby supplemented as follows:

           On March 5, 2004, Leucadia submitted a revised written proposal (the
"Proposal") to the special committee of the Company's Board of Directors.

           The Proposal provides for a transaction in which a to-be-formed
affiliate of Leucadia will acquire the Company in a merger for a combination of
cash and securities (the "Buyer Securities") described in the Proposal and
valued by Leucadia at approximately $18.19 per share, representing a 8.6%
premium to the $16.75 transaction between the Company, management of the Company
and Paul Allen (the "Insider Transaction"). A copy of the Proposal is attached
hereto as Exhibit 2 and incorporated herein by reference. A copy of the press
releases issued by Leucadia on March 5, 2004 and March 8, 2004 are attached
hereto as Exhibits 3, 4 and 5, and incorporated herein by reference.

           The Reporting Persons believe that the Proposal is superior to the
$16.75 Insider Transaction. The Reporting Persons have communicated the Proposal
to the Company's Board of Directors and the Reporting Persons intend to
communicate to other shareholders of the Company and other interested parties in
an effort to determine shareholder interest in the Proposal. The Reporting
Persons may acquire additional securities of the Company or dispose of
securities of the Company at any time and from time to time in the open market,
in privately negotiated transactions or otherwise.

           Although the foregoing represents the range of activities presently
contemplated by the Reporting Persons and, to their knowledge, their respective
general partners, directors and officers, as applicable, with respect to the
Company, it should be noted that the possible activities of the Reporting
Persons and their respective general partners, directors and officers are
subject to change at any time.

           Except as set forth above, neither the Reporting Persons, nor, to
their knowledge, any of their respective general partners, directors or
officers, have any present plans or proposals which relate to or would result in
any of the actions described in subparagraphs (a) through (j) of Item 4 of
Schedule 13D.

Item 7.    Materials to be Filed as Exhibits.

1.         Agreement among the Reporting Persons with respect to the filing of
           this Schedule 13D.

2.         Proposal, dated March 5, 2004, from Leucadia.



                                       6

3.         Press release of Leucadia National Corporation dated March 5, 2004,
           incorporated herein by reference to Exhibit 99.1 to Leucadia's
           Current Report on Form 8-K filed on March 8, 2004 (the "Leucadia
           8-K").

4.         Press release of Leucadia National Corporation dated March 5, 2004,
           incorporated herein by reference to Exhibit 99.2 to the Leucadia's
           8-K.

5.         Press release of Leucadia National Corporation dated March 8, 2004,
           incorporated herein by reference to Exhibit 99.3 to the Leucadia's
           8-K.



















                                       7

                                    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.


                              LEUCADIA NATIONAL CORPORATION

                              By: /s/ Joseph A. Orlando
                                  -----------------------------------------
                                  Name: Joseph A. Orlando
                                  Title: Vice President and
                                          Chief Financial Officer



                              PERSHING SQUARE, L.P.

                              By: PERSHING SQUARE GP, LLC

                              By: /s/ William Ackman
                                  -----------------------------------------
                                  Name: William Ackman
                                  Title: Managing Member



                              PERSHING SQUARE GP, LLC

                              By: /s/ William Ackman
                                  -----------------------------------------
                                  Name: William Ackman
                                  Title: Managing Member



                              By: /s/ William Ackman
                                  -----------------------------------------
                                  Name: William Ackman


Date: March 9, 2004



                                  EXHIBIT INDEX


Exhibit No.
-----------

Exhibit 1  -          Agreement among the Reporting Persons with respect to the
                      filing of this Schedule 13D

Exhibit 2  -          Proposal, dated March 5, 2004, from Leucadia

Exhibit 3  -          Press release of Leucadia National Corporation dated March
                      5, 2004, incorporated herein by reference to Exhibit 99.1
                      to Leucadia's Current Report on Form 8-K filed on March 8,
                      2004 (the "Leucadia 8-K")

Exhibit 4  -          Press release of Leucadia National Corporation dated March
                      5, 2004, incorporated herein by reference to Exhibit 99.2
                      to the Leucadia 8-K

Exhibit 5  -          Press release of Leucadia National Corporation dated March
                      8, 2004, incorporated herein by reference to Exhibit 99.3
                      to the Leucadia 8-K