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                                 EXHIBIT 10.79


                         AMENDMENT NO. 1 (the "Amendment") dated as of June 30,
                         1997 to the CREDIT, SECURITY, GUARANTY AND PLEDGE
                         AGREEMENT, dated as of December 20, 1996 (as amended by
                         the Waiver and Amendment dated as of February 20, 1997,
                         and as amended, supplemented or otherwise modified,
                         renewed or replaced from time to time, the "Credit
                         Agreement"), among TRIMARK PICTURES, INC., a California
                         corporation, and TRIMARK TELEVISION, INC., a Delaware
                         corporation (each a "Borrower" and together, the
                         "Borrowers"), the Guarantors named herein, the Lenders
                         referred to herein, THE CHASE MANHATTAN BANK, a New
                         York banking corporation, as Agent (the "Administrative
                         Agent") for the Lenders and THE CHASE MANHATTAN BANK as
                         Fronting Bank (the "Fronting Bank").


                             INTRODUCTORY STATEMENT
                             ----------------------


          The Borrowers and the Guarantors have requested that the Lenders amend
Sections 6.14 and 6.18 of the Credit Agreement, delete Section 6.19 from the
Credit Agreement and add certain additional Acceptable Obligors to Schedule 2 of
the Credit Agreement.  The Lenders are willing to comply with such request on
the terms and subject to the conditions hereinafter set forth.

          Accordingly, the parties hereto hereby agree as follows:

I.        Section   Defined Terms.  All capitalized terms not otherwise defined
                    -------------                                              
in this Amendment are used herein as defined in the Credit Agreement.

I.        Section   Amendment to the Credit Agreement.  Subject to the
                    ---------------------------------                 
satisfaction of the conditions in Section 3 hereof, the Credit Agreement is
hereby amended effective as of the date hereof, as follows:
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(1)       The definition of "Consolidated Total Liabilities" is hereby deleted
from the Credit Agreement in its entirety.

(1)       The definition of "Off-Balance Sheet Commitments" is hereby deleted
from the Credit Agreement in its entirety.

(1)       Article 1 of the Credit Agreement is hereby amended by adding the
following definition in the appropriate alphabetical sequence:

               "Product Acquisition Commitments" shall mean all commitments
                -------------------------------                            
          of the Credit Parties for the acquisition of items of Product,
          including cash flow commitments, negative pick-up obligations and
          print and advertising commitments, regardless of whether or not,
          pursuant to GAAP, reflected on the Consolidated balance sheet of the
          Parent and its Consolidated Subsidiaries; provided, however, that such
          obligations for print and advertising commitments shall not be
          included in Product Acquisition Commitments until principal
          photography has commenced for the item of Product to which each such
          commitment relates."

(1)            Section 5.1(c) of the Credit Agreement is hereby amended and
restated to read as follows:

               "Simultaneously with the delivery of the statements referred to
          in paragraphs (a) and (b) of this Section 5.1, a certificate of an
          Authorized Officer of the Parent, on behalf of the Parent, in form and
          substance satisfactory to the Administrative Agent (i) stating whether
          or not such Authorized Officer has knowledge, after due inquiry, of
          any condition or event which would constitute an Event of Default or
          Default has occurred and, if so, specifying each such condition or
          event and the nature thereof, (ii) demonstrating in reasonable detail
          compliance with the provisions of Sections 6.14 through 6.18 and 6.22
          hereof and (iii) certifying that all filings required under Section
          5.8 hereof have been made and listing each such filing that has been
          made since the date of the last certificate delivered in accordance
          with this Section 5.1(c);"
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(1)            Section 6.14 of the Credit Agreement is hereby amended and
restated to read as follows:

          "Permit Consolidated Tangible Net Worth at the end of any quarter to
          be less than the sum of $19,000,000 plus 100% of net new equity
          invested and 50% of net earnings, if any, for each fiscal year ending
          after June 30, 1996 and prior to the date as of which compliance is
          being determined."

(1)            Section 6.18 of the Credit Agreement is hereby amended and
restated to read as follows:

          "Section 6.18 Consolidated Tangible Net Worth Ratio.
                        ------------------------------------- 

          Permit the ratio of (i) the aggregate amount of all Indebtedness of
          the Parent and its Consolidated Subsidiaries, consolidated in
          accordance with GAAP, plus 100% of Product Acquisition Commitments of
          the Parent and its Consolidated Subsidiaries that support financings
          provided by the Lenders, plus 110% of all other Product Acquisition
          Commitments of the Parent and its Consolidated Subsidiaries, less the
          present value of related Off-Balance Sheet Receivables (but not more
          than the related portion of Product Acquisition Commitments), to (ii)
          Consolidated Tangible Net Worth to be greater than 3.5 to 1 at any
          time."

(1)            Section 6.19 of the Credit Agreement is hereby amended in its
entirety to read "Not Used".

(1)            Schedule 2 of the Credit Agreement is hereby amended by adding
under the heading "Acceptable Domestic Account Debtors (85%)" the following
Acceptable Domestic Account Debtor and corresponding Allowable Amount in the
appropriate numeric sequence:

          All American Communications                   2,000,000

(1)            Schedule 2 of the Credit Agreement is hereby amended by adding
under the heading "Acceptable Foreign Account Debtors (75%)" the following
Acceptable Foreign Account Debtors 
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and corresponding territories and Allowable Amounts in the appropriate numeric
sequence:

          Foxton              Germany    900,000
 
          Televisa, S.A.      Mexico     500,000
 
          Pony Canyon         Japan      400,000
 
          Golden Harvest      Taiwan     300,000
 
          Mongkol Cinema      Thailand   300,000


I.        Section   Conditions to Effectiveness.  The effectiveness of this
                    ---------------------------                            
Amendment is subject to the satisfaction in full of the following conditions
precedent.

(1)                 The Administrative Agent shall have received executed
          counterparts of this Amendment, which, when taken together, bear the
          signatures of each party hereto;
          
(1)                 An amendment fee in the amount of .125% of the Commitment of
          each Lender shall have been paid to the Administrative Agent on behalf
          of each Lender.
 
(1)                 All legal matters in connection with this Amendment shall be
          reasonably satisfactory to Morgan, Lewis & Bockius LLP, counsel for
          the Administrative Agent.

I.        Section   Representations and Warranties.  Each of the Credit Parties
                    ------------------------------                             
hereby represents, warrants and acknowledges to the Administrative Agent (on
behalf of itself, Fronting Bank and the Lenders) that:

(1)                 Their respective obligations to the Lenders under the Credit
          Agreement remain in full force and effect.

(1)                 The representations and warranties contained in the Credit
          Agreement and in the other Fundamental Documents are true and correct
          in all material respects on and as of the date hereof as if such
          representations and warranties had been 
<PAGE>
 
          made on and as of the date hereof (except to the extent such
          representations and warranties expressly relate to as an earlier
          date).

               (c)  After giving effect hereto, each of the Credit Parties is in
          compliance with all the terms and provisions set forth in the Credit
          Agreement and the other Fundamental Documents and no Default or Event
          of Default has occurred or is continuing under the Credit Agreement or
          any other Fundamental Document.

(1)                 The acknowledgments, representations and warranties in this
          Section 3 have been a material inducement for the Lenders to agree to
          enter into this Amendment, (ii) the Lenders are relying on such
          acknowledgments, representations and warranties, and (iii) the Lenders
          would not have entered into this Amendment without such
          acknowledgments, representations and warranties.
 
I.        Section     Full Force and Effect.  Except as expressly set forth
                      ---------------------                                
herein, this Amendment does not constitute a waiver or modification of any
provision of the Credit Agreement or a waiver of any Default or Event of Default
under the Credit Agreement, in either case whether or not known to the Lenders.
Except as expressly amended hereby, the Credit Agreement shall continue in full
force and effect in accordance with the provisions thereof on the date hereof.
As used herein, the terms "Credit Agreement", "this Agreement", "herein",
"hereafter", "hereto", "hereof", and words of similar import, shall, unless the
context otherwise requires, mean the Credit Agreement as amended by this
Amendment.  References to the terms "Agreement" or "Credit Agreement" appearing
in the Exhibits or Schedules hereto or to the Credit Agreement, shall, unless
the context otherwise requires, mean the Credit Agreement as amended by this
Amendment.

I.        SECTION   APPLICABLE LAW.  THIS AMENDMENT SHALL BE GOVERNED BY, AND
                    --------------                                           
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WHICH ARE
APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED WHOLLY WITHIN THE STATE OF NEW
YORK.

I.        Section   Counterparts.  This Amendment may be executed in two or more
                    ------------                                                
counterparts, each of which shall 
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constitute as an original, but all of which when taken together shall constitute
but one instrument.

I.        Section   Expenses.  The Borrowers agree to pay all reasonable out-of-
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pocket expenses incurred by the Administrative Agent in connection with the
preparation, execution, delivery, performance or enforcement of this Amendment,
the Credit Agreement or the other Fundamental Documents and any other
documentation contemplated hereby or thereby, including, but not limited to, the
reasonable fees and disbursements of external legal counsel for the
Administrative Agent and the allocated costs and charges of its internal legal
counsel.

I.        Section   Headings.  The headings of this Amendment are for the
                    --------                                             
purposes of reference only and shall not affect the construction of, or be taken
into consideration in interpreting, this Amendment.
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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their duly authorized officers, all as of the date and year
first written above.


                                    TRIMARK PICTURES, INC.       
                                    TRIMARK TELEVISION, INC.     
                                    TRIMARK HOLDINGS, INC.       
                                    TRIMARK MUSIC                
                                    CHEAP DATE, INC.             
                                    WRITERS ON THE WAVE          
                                    PURPLE TREE PRODUCTIONS, INC.
                                    LOVING GUN PRODUCTIONS, INC. 
                                    TRIMARK INTERACTIVE           


                                    By____________________________
                                      Name:
                                      Title:  Authorized Signatory 
                                              for each of the foregoing


                                    THE CHASE MANHATTAN BANK,    
                                    individually and as
                                    Administrative Agent


                                    By:___________________________
                                       Name:
                                       Title:


                                    CITY NATIONAL BANK


                                    By:___________________________
                                       Name:
                                       Title:


                                    COMERICA BANK-CALIFORNIA


                                    By:___________________________
                                       Name:
                                       Title:


                                    FIRST HAWAIIAN BANK


                                    By:___________________________
                                       Name:
<PAGE>
 
                                       Title:


                                    IMPERIAL BANK


                                    By:___________________________
                                       Name:
                                       Title:


                                    SILICON VALLEY BANK


                                    By:___________________________
                                       Name:
                                       Title:


                                    THE SUMITOMO TRUST & BANKING CO., LTD., 
                                    NEW YORK BRANCH


                                    By:___________________________
                                       Name:
                                       Title:


                                    UNION BANK OF CALIFORNIA, N.A.


                                    By:___________________________
                                       Name:
                                       Title:


                                    DE NATIONALE INVESTERINGSBANK N.V.


                                    By:___________________________
                                       Name:
                                       Title: