<PAGE>
 
                                                                    EXHIBIT 10.4

                                  AMENDMENT I
                   TO AMENDED AND RESTATED CREDIT AGREEMENT
                                       
     AMENDMENT I dated as of March 30, 1998 to the Amended and Restated Credit
Agreement dated as of October 15, 1997 (the "CREDIT AGREEMENT") among METRO-
GOLDWYN-MAYER STUDIOS INC. ("MGM"), ORION PICTURES CORPORATION ("ORION" and,
together with MGM, the "BORROWERS"), the LENDERS listed on the signature pages
thereof, the L/C ISSUERS named therein, MORGAN GUARANTY TRUST COMPANY OF NEW
YORK, as Agent (the "AGENT") and BANK OF AMERICA NATIONAL TRUST AND SAVINGS
ASSOCIATION, as Syndication Agent.

                                  WITNESSETH:

     WHEREAS, the parties hereto desire to amend the Credit Agreement to modify 
certain financial covenants;

     NOW, THEREFORE, the parties hereto agree as follows:

     SECTION 1.  Definitions; References.  Unless otherwise specifically defined
herein, each term used herein which is defined in the Credit Agreement has the 
meaning assigned to such term in the Credit Agreement.  Each reference to 
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Credit Agreement shall, from and after the date hereof, refer
to the Credit Agreement as amended hereby.

     SECTION 2.  Amendment to "Adjusted EBITDA to Cash Interest Expense" 
Covenant.  Section 5.11 of the Credit Agreement is amended by restating the 
first three rows of the table set forth therein to read as follows:

<TABLE> 
                     <S>                 <C> 
                     03/31/98            1.10:1
                     06/30/98            1.10:1
                     09/30/98            1.10:1
</TABLE> 

     SECTION 3.  Amendment to "Total Borrowed Funds to Adjusted EBITDA" 
Covenant.  Section 5.12 of the Credit Agreement is amended by deleting the first
four rows (from the row beginning "03/31/98" through and including the row 
beginning "12/31/98") of the table set forth therein.
<PAGE>
 
     SECTION 4.  No Waiver. This Amendment shall not operate as a waiver of 
any right, remedy, power or privilege of the Lenders under any Loan Document or 
of any other term or condition thereof.

     SECTION 5. Representations of Borrowers. Each of the Borrowers represents 
and warrants that, on and as of the Amendment Effective Date (as hereinafter 
defined) and after giving effect to this Amendment, (i) the representations and 
warranties of the Obligors set forth in the Loan Documents will be true and 
correct in all respects and (ii) no Default will have occurred and be 
continuing.

     SECTION 6. Governing Law. This Amendment shall be governed by and construed
in accordance with the laws of the State of New York.

     SECTION 7. Counterparts. This Amendment may be signed in any number of 
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

     SECTION 8. Effectiveness. This Amendment shall become effective as of the 
date hereof on the date (the "AMENDMENT EFFECTIVE DATE") when the Agent shall 
have received from each of the Borrowers and the Required Lenders a counterpart 
hereof signed by such party or facsimile or other written confirmation (in form 
satisfactory to the Agent) that such party has signed a counterpart hereof.

                                       2
<PAGE>
 
     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.


                                   METRO-GOLDWYN-MAYER
                                    STUDIOS INC.



                                   By: /s/ Michael G. Corrigan
                                       -------------------------------------- 
                                       Title: Senior Executive Vice President
                                              and Chief Financial Officer



                                   ORION PICTURES CORPORATION



                                   By: /s/ Michael G. Corrigan
                                       --------------------------------------  
                                       Title: Senior Executive Vice President
                                              and Chief Financial Officer

                                   MORGAN GUARANTY TRUST
                                    COMPANY OF NEW YORK, as Agent
                                    and as Lender



                                   By: /s/ R. Blake Witherington
                                       --------------------------------------
                                       Title: Vice President



                                   BANK OF AMERICA NATIONAL TRUST
                                    AND SAVINGS ASSOCIATION, as
                                    Syndication Agent and as Lender



                                   By: /s/ Matthew J. Koening
                                       --------------------------------------
                                       Title: Vice President 
 
                                       3
<PAGE>
 
                                   THE CHASE MANHATTAN BANK


                                   By:  /s/ John W. Miller
                                       ------------------------------------
                                       Title: Managing Director



                                   SOCIETE GENERALE
                                   
                                   
                                   By: ____________________________________
                                       Title:
                                   
                                   
                                   
                                   THE BANK OF NOVA SCOTIA
                                   
                                   
                                   By:  /s/ Alan Pendergast
                                       ------------------------------------
                                       Title: Relationship Manager
                                   
                                   
                                   
                                   VAN KAMPEN AMERICAN CAPITAL
                                    PRIME RATE INCOME TRUST
                                   
                                   
                                   By:  /s/ Jeffrey W. Maillet
                                       ------------------------------------
                                       Title: Senior Vice President & Director
                                   
                                   
                                   
                                   FLEET NATIONAL BANK
                                   
                                   
                                   By: ____________________________________
                                       Title:
                                   
                                       4
<PAGE>
 
                                   ING (U.S.) CAPITAL CORPORATION

                               
                                   By: _______________________________
                                       Title:

                                   ING HIGH INCOME PRINCIPAL
                                     PRESERVATION FUND HOLDINGS, LDC

                                   By ING Capital Advisors, Inc., as
                                     Investment Advisor

                                   By: /s/ Michael D. Hatley
                                       -------------------------------
                                       Title: Vice President & Portfolio Manager
                                          

                                   KZH-ING-1 CORPORATION


                                   By: _______________________________
                                       Title:


                                   ARCHIMEDES FUNDING LLC


                                   By ING Capital Advisors, Inc., as
                                     Collateral Manager


                                   By: /s/ Michael D. Hatley
                                       --------------------------------
                                       Title: Vice President & Portfolio Manager



                                       5
<PAGE>
 
                                   MERRILL LYNCH SENIOR FLOATING
                                    RATE FUND, INC.

                                   By: __________________________
                                       Title:


                                   
                                   SENIOR HIGH INCOME PORTFOLIO, INC.


                                   By: __________________________
                                       Title:



                                   DEBT STRATEGIES FUND, INC.


                                   By: __________________________
                                       Title:



                                   THE BANK OF NEW YORK


                                   By: __________________________
                                       Title:



                                   BANK OF SCOTLAND


                                   By: /s/ Annie Chin Tat
                                       __________________________
                                       Title: Vice President



 
                                       6
<PAGE>
 


                                   THE INDUSTRIAL BANK OF JAPAN,               
                                     LIMITED, LOS ANGELES AGENCY              
                                                                              
                                                                              
                                   By:  /s/ Vicente L. Timiraos               
                                        --------------------------------------
                                        Title:  Senior Vice President & Senior
                                                Deputy General Manager        
                                                                              
                                                                              
                                   THE LONG-TERM CREDIT BANK OF               
                                     JAPAN, LTD., LOS ANGELES                 
                                     AGENCY                                   
                                                                              
                                                                              
                                   By:  /s/ Noboru Akahane                    
                                        --------------------------------------
                                        Title:  Deputy General Manager        
                                                                              
                                                                              
                                   UNION BANK OF CALIFORNIA                   
                                                                              
                                                                              
                                   By:  /s/ Thomas P. Garry, Jr.              
                                        --------------------------------------
                                        Title:  Assistant Vice President      
                                                                              
                                                                              
                                   GENERAL ELECTRIC CAPITAL                   
                                     CORPORATION                              
                                                                              
                                                                              
                                   By:  /s/ Janet K. Williams                 
                                        --------------------------------------
                                        Title:  Duly Authorized Signatory     
                                                                              
                                                                              
                                   For ARAB BANKING CORPORATION               
                                     NEW YORK BRANCH                          
                                                                              
                                                                              
                                   By:  /s/ Richard B. Whelan                 
                                        --------------------------------------
                                        Title:  Vice President & Manager      
                                                Los Angeles Representative    
                                                Office                        

                                       7
<PAGE>
 
                                   BANK OF HAWAII
                                   
                                   
                                   By:  /s/ Elizabeth O. MacLean
                                       ---------------------------------------
                                       Title: Vice President
                                   
                                   
                                   
                                   PILGRIM AMERICA PRIME RATE
                                     TRUST
                                   
                                   
                                   By Pilgrim America Investments, Inc., as its
                                      Investment Manager
                                   
                                   
                                   By:  /s/ Thomas C. Hunt
                                       ---------------------------------------
                                       Title: Assistant Portfolio Manager
                                   
                                   
                                   
                                   SANWA BUSINESS CREDIT
                                     CORPORATION
                                   
                                   
                                   By:  /s/ Raffi Shirinyan
                                       ---------------------------------------
                                       Title: Vice President
                                   
                                   
                                   
                                   GULF INTERNATIONAL BANK B.S.C.
                                   
                                   
                                   By:  /s/ Abdel-Fattah Tahoun
                                       ---------------------------------------
                                       Title: Senior Vice President
                                   
                                   
                                   By:  /s/ Haytham F. Khalil
                                       ---------------------------------------
                                       Title: Assistant Vice President

                                       8
<PAGE>
 
                                                MASSACHUSETTS MUTUAL LIFE
                                                  INSURANCE COMPANY


                                                By: /s/ Richard E. Spencer II
                                                    ------------------------
                                                    Title: Managing Director


 
                                               BANQUE WORMS CAPITAL
                                                  CORPORATION


                                                By: /s/ Frederic Gamet
                                                    ------------------------
                                                    Title: Senior Vice President
                                        

                                                By: /s/ Constance de Klerk
                                                    ------------------------
                                                    Title: Vice President



                                                CITY NATIONAL BANK, a National
                                                  Banking Association


                                                By: /s/ Richard V. McCune
                                                    ------------------------
                                                    Title: Vice President


                                                FIRST HAWAIIAN BANK


                                                By: /s/ Donald C. Young
                                                    ------------------------
                                                    Title: Vice President

                                       9
<PAGE>
 

                                   INDOSUEZ CAPITAL FUNDING III,               
                                     LIMITED
                                                                              
                                   By Indosuez Capital, as Portfolio Advisor


                                   By:  
                                       --------------------------------------
                                       Title:  
                                                
                                                                              
                                   CITIBANK, N.A.
                                                                              
                                                                              
                                   By: /s/ Hans L. Christensen               
                                       --------------------------------------
                                       Title:  Vice President
                                                                              
                                                                              
                                   PACIFIC LIFE INSURANCE COMPANY             
                                                                              
                                                                              
                                   By: /s/ Raymond J. Lee
                                       --------------------------------------
                                       Title:  Senior Vice President
                                                                              
                                                                              
                                   By: /s/ Elaine M. Havens
                                       --------------------------------------
                                       Title:  Vice President
                                                                              
                                                                              
                                   PFL LIFE INSURANCE COMPANY                 
                                                                              
                                                                              
                                   By: /s/ Gregory W. Theobald               
                                       --------------------------------------
                                       Title:  Vice President & Assistant    
                                               Secretary
                                                
                                      10

<PAGE>
 
                                         PRIME INCOME TRUST


                                         By:/s/ Sheila A. Finnerty
                                            -----------------------------------
                                            Title: Vice President

                        
                                         PAMCO CAYMAN LTD.
                                              
                                         By Protective Asset Management Company,
                                            as Collateral Manager


                                         By:/s/ James Dondero
                                            -----------------------------------
                                            Title: President, Protective Asset
                                                   Management Company


                                         MERRILL LYNCH, PIERCE, FENNER &
                                           SMITH INCORPORATED


                                         By:/s/ Neil Brisson
                                            -----------------------------------
                                            Title: Director


                                         KZH-ING-2 CORPORATION
                                                

                                         By:
                                            -----------------------------------
                                            Title:


                                         MORGAN STANLEY SENIOR
                                           FUNDING, INC.

                                         By:
                                            ----------------------------------
                                            Title: 

                                      11
<PAGE>
 
                                   CONTINENTAL ASSURANCE COMPANY
                                     SEPARATE ACCOUNT (E)

                                   By Protective Asset Management Company,
                                      as Attorney-in-Fact



                                   By:/s/ James Dondero
                                      ---------------------------------------
                                      Title: President, Protective Asset
                                             Management Company



                                   ML CBO IV (CAYMAN) LTD.

                                   By Protective Asset Management Company,
                                      as Collateral Manager



                                   By:/s/ James Dondero
                                      ---------------------------------------
                                      Title: President, Protective Asset
                                             Management Company


                                   SENIOR DEBT PORTFOLIO

                                   By Boston Management & Research, as
                                      Investment Advisor


                                   By:/s/ Payson F. Swaffield
                                      ---------------------------------------
                                      Title: Vice President



                                   ML CLO XII PILGRIM AMERICA
                                    (CAYMAN) LTD. (as assignee)

 
                                   By Pilgrim America Investments, Inc., as its
                                     Investment Manager


                                   By:/s/ Thomas C. Hunt
                                      ---------------------------------------
                                      Title: Assistant Portfolio Manager  



                                      12
<PAGE>
 
                                   CYPRESSTREE INVESTMENT
                                     PARTNERS I, LIMITED
                                   
                                   
                                   By CypressTree Investment Management
                                      Company, as Portfolio Manager
                                   
                                   
                                   By:  /s/ Catherine C. McDermott
                                       -----------------------------------
                                       Title: Principal
                                   
                                   
                                   
                                   MERRILL LYNCH PRIME RATE 
                                     PORTFOLIO
                                   
                                   
                                   By: ___________________________________
                                       Title:
                                   
                                   
                                   
                                   MERRILL LYNCH DEBT STRATEGIES
                                     PORTFOLIO
                                   
                                   
                                   By: ___________________________________
                                       Title:
                                   
                                   
                                   
                                   ABN AMRO BANK N.V.
                                   
                                   
                                   By:  /s/ Frances O'R. Logan
                                       -----------------------------------
                                       Title: Group Vice President
                                   
                                   
                                   By:  /s/ William S. Bennett
                                       -----------------------------------
                                       Title: Vice President
                                   
                                      13

<PAGE>
 

                                   BDC FINANCE LLC
                                                                              
                                                                              
                                   By:  
                                        --------------------------------------
                                        Title:  
                                                
                                                                              
                                   NATEXIS BANQUE - BFCE
                                                                              
                                                                              
                                   By:  /s/ Daniel Touffu                     
                                        --------------------------------------
                                        Title:  First Vice President and 
                                                Regional Manager
                                                                              
                                                                              
                                   By:  /s/ Joan M. Farrell
                                        --------------------------------------
                                        Title:  Assistant Vice President      
                                                                              
                                                                              
                                   FC CBO LIMITED
                                                                              
                                                                              
                                   By:  
                                        --------------------------------------
                                        Title:  
                                                                              
                                                                              
                                   FREMONT FINANCIAL
                                     CORPORATION                              
                                                                              
                                                                              
                                   By:  /s/ Cheri Rittman
                                        --------------------------------------
                                        Title:  Vice President 
                                               
 
                                   THE FUJI BANK, LIMITED


                                   By:  /s/ Masahito Fukuda
                                        --------------------------------------
                                        Title:  Joint General Manager

                                      14

<PAGE>
 
                                   GOLDMAN SACHS CREDIT PARTNERS L.P.


                                   By: /s/ Stephen J. McGuinness
                                       ----------------------------
                                       Title: Authorized Signatory



                                   THE SUMITOMO BANK, LIMITED

                                   
                                   By: /s/ B. Smith
                                       ---------------------------- 
                                       Title: Senior Vice President


                                   By: /s/ J.H. Broadley
                                       ---------------------------- 
                                       Title: Vice President


                                   THE TORONTO-DOMINION BANK


                                   By: /s/ David G. Parker
                                       ---------------------------- 
                                       Title: Manager, Credit Administration


                                   KEYPORT LIFE INSURANCE COMPANY

                                 
                                   By: /s/ Brian W. Good
                                       ---------------------------- 
                                       Title: Vice President & Portfolio Manager

                          
                                   THE ING CAPITAL SENIOR SECURED
                                    HIGH INCOME FUND, L.P.

                                   By ING Capital Advisors, Inc., as
                                     Investment Advisor

                          
                                   By: /s/ Michael D. Hatley
                                       ---------------------------- 
                                       Title: Vice President & Portfolio Manager

                                      15