EXHIBIT 99.2
 
                                  VIACOM INC.,
 
                           VIACOM INTERNATIONAL INC.,
 
                      VIACOM INTERNATIONAL SERVICES INC.,
 
                                      AND
 
                      STATE STREET BANK AND TRUST COMPANY,
                                    TRUSTEE
 
                               ----------------
 
                          THIRD SUPPLEMENTAL INDENTURE
 
         DATED AS OF JULY 22, 1996 TO BE EFFECTIVE AS OF JULY 31, 1996
 
   TO INDENTURE DATED AS OF MAY 15, 1995 AMONG VIACOM INC.,VIACOM INTERNATIONAL
                INC.AND THE FIRST NATIONAL BANK OF BOSTON,TRUSTEE
 
                               ----------------
 
                             SENIOR DEBT SECURITIES

 
  THIRD SUPPLEMENTAL INDENTURE, dated as of July 22, 1996, to be effective as
of July 31, 1996, among VIACOM INC., a Delaware corporation (the "Company"),
VIACOM INTERNATIONAL INC., a Delaware corporation (the "Guarantor"), VIACOM
INTERNATIONAL SERVICES INC. (the "Successor"), and STATE STREET BANK AND TRUST
COMPANY, a Massachusetts trust company, as successor to The First National
Bank of Boston (the "Trustee"), as Trustee to the Indenture, dated as of May
15, 1995, among the Company, the Guarantor and the Trustee, as supplemented by
the First Supplemental Indenture, dated as of May 24, 1995, among the Company,
the Guarantor and the Trustee and as further supplemented and amended by the
Second Supplemental Indenture and Amendment No. 1, dated as of December 15,
1995, among the Company, the Guarantor and the Trustee (as amended, the
"Indenture").
 
                                   RECITALS
 
  WHEREAS, the Company, the Guarantor and the Trustee are parties to the
Indenture, pursuant to which the Company has issued $1 billion principal
amount of 7.75% Senior Notes due 2005, $350 million principal amount of 6.75%
Senior Notes due 2003 and $200 million principal amount of 7.625% Senior
Debentures due 2016 (the "Securities");
 
  WHEREAS, pursuant to the Indenture the Guarantor has unconditionally
guaranteed the Securities (the "Guarantees");
 
  WHEREAS, the Guarantor and the Successor are parties to an Implementation
Agreement dated as of July 24, 1995 (the "Implementation Agreement") pursuant
to which the Guarantor shall convey substantially all of its assets to the
Successor (the "Conveyance of Assets") and the Successor shall assume
substantially all of the liabilities of the Guarantor, including liabilities
in respect of the Securities (the "Assumption of Liabilities");
 
  WHEREAS, the Guarantor and the Successor desire, pursuant to Section 901 of
the Indenture, to supplement and amend the Indenture, in order to comply with
Section 801 of the Indenture;
 
  WHEREAS, the Successor is a corporation validly existing under the laws of
the State of Delaware;
 
  WHEREAS, the Successor has duly authorized the execution and delivery of
this Third Supplemental Indenture to assume all the covenants and conditions
of the Guarantor under the Guarantees and the Indenture; and
 
  WHEREAS, immediately after the consummation of the Conveyance of Assets and
Assumption of Liabilities in accordance with the Implementation Agreement, no
Event of Default or Default (as defined in the Indenture) shall have occurred
and be continuing.
 
  NOW, THEREFORE, the Company, the Guarantor, the Successor and the Trustee
covenant and agree as follows:
 
                                   ARTICLE A
 
  SECTION A.1. The Successor hereby assumes all the covenants and conditions
of the Guarantor under the Guarantees and the Indenture; and the Successor
shall succeed to, and be substituted for, and may exercise every right and
power of, the Guarantor under the Indenture with the same effect as if the
Successor had been named as the Guarantor therein; and the Guarantor shall be
relieved of all covenants and conditions under the Guarantees and the
Indenture.
 
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                                   ARTICLE B
 
                           MISCELLANEOUS PROVISIONS
 
  SECTION B.1 Any notice or communication by the Trustee to the Successor is
duly given if in writing and delivered in person or mailed by first-class mail
to the address set forth below:
 
                                   Viacom International Services Inc.1515
                                   BroadwayNew York, NY 10036Attention: Chief
                                   Financial Officer, with a copy to
the Office of the General Counsel
 
  SECTION B.2. THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THIS THIRD
SUPPLEMENTAL INDENTURE.
 
  SECTION B.3. This Third Supplemental Indenture may be executed in any number
of counterparts, each of which when so executed shall be deemed to be an
original, but such counterparts shall together constitute but one and the same
instrument.
 
  IN WITNESS WHEREOF, the parties have caused this Third Supplemental
Indenture to be duly executed as of the day and year first written above.
 
                                          VIACOM INC.
 
                                                  /s/ Michael D. Fricklas
                                          By___________________________________
                                                 Name: Michael D. Fricklas
                                               Title: Senior Vice President
                                            Deputy General Counsel
 
                                          VIACOM INTERNATIONAL INC.
 
                                                  /s/ Michael D. Fricklas
                                          By___________________________________
                                                 Name: Michael D. Fricklas
                                               Title: Senior Vice President
                                            Deputy General Counsel
 
                                          VIACOM INTERNATIONAL SERVICES INC.
 
                                                  /s/ Michael D. Fricklas
                                          By___________________________________
                                                 Name: Michael D. Fricklas
                                               Title: Senior Vice President
                                            Deputy General Counsel
 
                                          STATE STREET BANK AND TRUST COMPANY
 
                                                   /s/ Eric L. Donaghey
                                          By___________________________________
                                            Name: Eric L. Donaghey
                                              Title: Assistant Vice President
 
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