EMPLOYMENT LETTER AGREEMENT
 
 
                                                                 EXECUTION COPY
 
                                   VIACOM INC.
 
                                 March 20, 2003
 
Sumner M. Redstone
New York, New York
 
Dear Mr. Redstone:
 
          Effective as of May 5, 2003 (the "Effective Date"), you will continue
to be employed as Chief Executive Officer of Viacom, Inc. ("Viacom") and serve
as Chairman of the Board of Directors of Viacom (the "Board") pursuant to the
terms of this letter agreement (the "Agreement").
 
          1. Duties. During your employment with Viacom, you will perform such
duties and have such responsibilities and authority as set forth hereunder:
 
          You, in consultation with Mel Karmazin, the President and Chief
Operating Officer of Viacom (the "COO"), will be generally responsible for
overseeing the affairs of Viacom and will have full and final-decision making
authority over corporate policy and strategy. The COO will report directly and
solely to you. You also will have the authority to overrule the COO on operating
matters, subject to the Board consultation provisions set forth below. For this
purpose, "corporate policy and strategy" means significant acquisitions,
significant dispositions, significant partnerships or ventures with other
companies, significant shareholder relations and corporate governance matters,
the entry into significant new lines of business and withdrawal from significant
existing lines of business, and other matters of comparable significance to
Viacom. The COO, in consultation with you, will have full authority over the
operations of Viacom. At any time during the term of the COO's employment, you
may recommend to the Board that the COO should be terminated. All officers,
other than you and the COO, will report directly or indirectly to the COO. The
COO will keep you advised of significant operating or organizational issues,
including, without limitation, the hiring and firing of senior executives,
provided that solely with regard to the firing of a group of senior executives
to be mutually agreed by you and the COO, and the hiring of their replacements,
you and the COO will agree jointly on such actions. The COO will ensure that you
will have full access to Viacom's executives, to staff meetings convened by the
COO, and to information and reports compiled by management so that you can fully
perform your responsibilities as Chief Executive
 
 
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Officer and are fully briefed on operating issues and the business of Viacom. It
is intended and expected that you will participate actively in such staff
meetings. You will have the right to overrule the COO's decision on any
operating issue only following prior consultation with the Board at a meeting
called for such purpose to provide the Board with the full opportunity to take
any action it deems appropriate with respect to such operating issue.
 
          2. Compensation. As the sole compensation for services to be rendered
by you in all capacities to Viacom, its subsidiaries and affiliates, you will
receive the following compensation by Viacom.
 
          (a) Salary: For all the services rendered by you in any capacity to
Viacom, its subsidiaries and affiliates, Viacom agrees to pay you a base salary
at the rate of $1,000,000 per annum ("Salary"), payable in accordance with
Viacom's then effective payroll practices.
 
          (b) Bonus Compensation: In addition to your Salary, you shall be
entitled to receive bonus compensation for each of the calendar years during
your employment with Viacom, determined and payable as follows ("Bonus"):
 
          (i)  Your Bonus for each of the calendar years during your employment
               with Viacom will be based upon a measurement of performance
               against objectives in accordance with Viacom's Short-Term
               Incentive Plan and its Senior Executive Short-Term Incentive
               Plan, as the same may be amended from time to time (collectively,
               the "STIP"), which objectives shall be no less favorable to you
               than the objectives used to determine the amount of bonus payable
               to any other executive of Viacom whose bonus is based in whole or
               in part on corporate performance and who participates in the
               STIP.
 
          (ii) Your Target Bonus for 2003 shall be $6,655,000, and for each
               calendar year thereafter shall be at least equal to the Target
               Bonus for the COO.
 
          (iii) Your Bonus for any calendar year shall be payable by February 28
               of the following year (even if not during your employment with
               Viacom).
 
          (c) Deferred Compensation: In addition to your Salary and Bonus, you
shall earn, in respect of calendar year 2003 and each calendar year thereafter
during your employment with Viacom, an additional amount ("Deferred
Compensation"), the payment of which (together with the return thereon as
provided in this paragraph 2(c)) shall be deferred until January of the first
calendar year following the year in which you cease to be an "executive officer"
of Viacom, as defined for purposes of the Securities Exchange Act of 1934, as
amended. The amount of Deferred Compensation for calendar year 2003 shall be
$2,993,000. The amount of Deferred Compensation for each subsequent calendar
year of your employment shall be the amount of Deferred Compensation for the
preceding year increased by an amount equal to 10% of the sum of your Salary and
Deferred Compensation for the preceding year. Deferred Compensation shall be
credited to a bookkeeping account maintained by Viacom on your behalf, the
balance of which account shall periodically be credited (or debited) with deemed
positive (or negative) return calculated in the same manner, and at the same
times, as the deemed return on your account under the excess 401(k) plan of
Viacom (as such plan may be amended from time to
 
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time) is determined or, if you do not participate in such plan, with a return to
be mutually agreed by Viacom and you. Viacom's obligation to pay the Deferred
Compensation (including the return thereon provided for in this paragraph 2(c))
shall be an unfunded obligation to be satisfied from the general funds of
Viacom.
 
          (d) Except as expressly provided herein, your compensation shall be
determined by the Compensation Committee of the Board.
 
          3. Benefits.
 
          (a) You shall be entitled to participate in such medical, dental and
life insurance, 401(k), pension and other plans as Viacom may have or establish
from time to time and in which any other Viacom executives are eligible to
participate. The foregoing, however, shall not be construed to require Viacom to
establish any such plans or to prevent the modification or termination of such
plans once established, and no such action or failure thereof shall affect this
Agreement; provided, however, that no modification of any plans in which you
participate shall be made which results in treating you less favorably than
other senior executives of Viacom. It is further understood and agreed that all
benefits (including without limitation, Viacom's Pension and Excess Pension
Plans, short term disability program, Long-Term Disability program and any
supplement thereto, life insurance and any applicable death benefit) you may be
entitled to as an employee of Viacom shall be based upon your Salary and, your
Deferred Compensation, as set forth in paragraphs 2(a) and (c) hereof, and not
upon any bonus compensation due, payable or paid to you hereunder, except where
the benefit plan expressly provides otherwise. You shall be entitled to four (4)
weeks vacation.
 
          (b) Viacom shall provide you with no less than Five Million Dollars
($5,000,000) of term life insurance during your employment with Viacom. You
shall have the right to assign the policy for such life insurance to your
spouse, if any, or issue or to a trust or trusts primarily for the benefit of
your spouse, if any, and/or issue.
 
          4. Business Expenses. During your employment with Viacom, you shall be
reimbursed for such reasonable travel and other expenses incurred in the
performance of your duties hereunder on a basis no less favorable than as
provided by Viacom to any of its senior executives.
 
          5. Perquisites. You shall be eligible for all perquisites made
available by Viacom from time to time during your employment with Viacom to any
other senior executives of Viacom. Without limiting the generality of the
foregoing, you shall be entitled to (i) a car allowance and insurance in
accordance with Viacom's policy and (ii) use of a private airplane in accordance
with Viacom policy on a basis no less favorable than as provided by Viacom to
any of its senior executives.
 
          6. Indemnification.
 
          (a) Viacom shall indemnify and hold you harmless, to the maximum
extent permitted by law and by the Certificate of Incorporation and/or the
Bylaws of Viacom, against judgments, fines, amounts paid in settlement of and
reasonable expenses incurred by you in
 
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connection with the defense of any action or proceeding (or any appeal
therefrom) in which you are a party by reason of your position as Chief
Executive Officer and Chairman of the Board or any other office you may hold
with Viacom or its affiliates or by reason of any prior positions held by you
with Viacom or any of its affiliates or predecessors or for any acts or
omissions made by you in good faith in the performance of any of your duties as
an officer of Viacom.
 
          (b) To the extent that Viacom maintains officers' and directors'
liability insurance, you will be covered under such policy.
 
          7. Notices. All notices required to be given hereunder shall be given
in writing, by personal delivery or by mail at the respective addresses of the
parties hereto set forth above, or at such other address as may be designated in
writing by either party. Any notice given by mail shall be deemed to have been
given three days following such mailing.
 
          8. Assignment. This is an Agreement for the performance of personal
services by you and may not be assigned by you or Viacom except that Viacom may
assign this Agreement to any affiliate of or any successor in interest to
Viacom.
 
          9. New York Law, Etc. This Agreement and all matters or issues
collateral thereto shall be governed by the laws of the State of New York
applicable to contracts entered into and performed entirely therein. Any action
to enforce this Agreement shall be brought in the state or federal courts
located in the City of New York. If you obtain any money judgment or otherwise
prevail in the final adjudication of any claim or suit brought by you or Viacom
to enforce or interpret any material provision contained herein, Viacom shall
reimburse you for any costs or expenses reasonably incurred by you (including
reasonable attorney's fees) in connection with such claim or suit.
 
          10. No Implied Contract. Nothing contained in this Agreement shall be
construed to impose any obligation on Viacom to renew this Agreement or any
portion thereof. The parties intend to be bound only upon execution of a written
agreement and no negotiation, exchange of draft or partial performance shall be
deemed to imply an agreement. Neither the continuation of employment nor any
other conduct shall be deemed to imply a continuing agreement upon the
expiration of this Agreement.
 
          11. Written Instrument. This Agreement can be changed only by a
writing signed by both parties hereto.
 
          12. Void Provisions. If any provision of this Agreement, as applied to
either party or to any circumstances, shall be adjudged by a court to be void or
unenforceable, the same shall be deemed stricken from this Agreement and shall
in no way affect any other provision of this Agreement or the validity or
enforceability of this Agreement.
 
          13. Supersedes Previous Agreements. Effective as of the Effective
Date, this Agreement shall supersede and cancel all prior agreements relating to
your employment by Viacom or any of its affiliates and predecessors, including,
without limitation, the letter agreement, dated September 6, 1999 between Viacom
and you. Notwithstanding the preceding
 
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sentence, this Agreement is not intended, and shall not be construed, to affect
your rights in any compensation or benefits that have been granted or accrued
prior to the Effective Date.
 
          14. Expiration of Article XIII. The parties hereto acknowledge and
agree that the special governance provisions of Article XIII of the Amended and
Restated Certificate of Incorporation of Viacom, including the super-majority
Board approval requirements contained therein, shall expire on May 4, 2003.
 
          If you agree with the foregoing terms, please execute this letter in
the space provided below and return a copy to the undersigned.
 
                                             VIACOM INC.
 
                                             By: /s/ MICHAEL D. FRICKLAS
                                                 --------------------------
                                                 Michael D. Fricklas
                                                 Executive Vice President,
                                                 General Counsel and Secretary
 
ACCEPTED AND AGREED:
 
/s/ SUMNER M. REDSTONE
------------------------
Sumner M. Redstone
March 20, 2003