Exhibit 10(a)

VIACOM
EXCESS 401(k) PLAN
FOR DESIGNATED SENIOR EXECUTIVES
EFFECTIVE AUGUST 28, 2002

Section 1.    Establishment and Purpose of the Plan.

        1.1    Establishment.    There is hereby established for the benefit of
Participants an unfunded plan of voluntarily deferred compensation known as the
Viacom Excess 401(k) Plan for Designated Senior Executives. Participation in
this Plan is limited to employees of an Employer who are identified by the
Company as executive officers and directors for purposes of Section 16(b) of the
Securities Act of 1934 ("Reporting Employees"). Any deferrals made under the
Viacom Excess 401(k) Plan by any Eligible Employee who was a participant in the
Viacom Excess 401(k) Plan prior to the date he becomes a Reporting Employee
shall remain in the Viacom Excess 401(k) Plan, subject to the terms of that
plan.

        1.2    Purpose.    The purpose of this Plan is to provide a means by
which an Eligible Employee may, in certain circumstances, elect to defer receipt
of a portion of his Compensation. The Plan also provides that the Company will,
in certain instances, credit the Account of a Participant with an Employer
Match.

Section 2.    Definitions.

        The following words and phrases as used in this Plan have the following
meanings:

        2.1    Account.    The term "Account" shall mean a Participant's
individual account, as described in Section 4 of the Plan.

        2.2    Board of Directors.    The term "Board of Directors" means the
Board of Directors of the Company.

        2.3    Bonus.    The term "Bonus" means any cash bonus paid under the
Viacom Inc. Short-Term Incentive Plan and any other comparable annual cash bonus
plan sponsored by any Employer.

        2.4    Committee.    The term "Committee" means the Retirement Committee
appointed by the Board of Directors. The Committee may act on its own behalf or
through the actions of its duly authorized delegate.

        2.5    Company.    The term "Company" means Viacom Inc.

        2.6    Compensation.    The term "Compensation" means an Eligible
Employee's annual compensation as defined in the Viacom 401(k) Plan, except that
the limitations imposed by Internal Revenue Code §401(a)(17) shall not be taken
into account.

        2.7    Eligible Employee.    The term "Eligible Employee" means an
Employee of an Employer who (i) has annual base salary payable at a rate equal
to or greater than the annual compensation limit in effect under Internal
Revenue Code Section 401(a)(17) of the Code (as adjusted from time to time by
the Committee) and (ii) is designated by the Committee as an employee who is
eligible to participate in the Plan. If an employee becomes an Eligible Employee
in any Plan Year, such employee shall remain an Eligible Employee for all future
Plan Years; provided, however, that the Committee may terminate such employee's
eligibility for the Plan if his annual base salary as of January 1, of any Plan
Year is less than the amount in clause (i) in effect for the Plan Year in which
such employee initially became an Eligible Employee. Notwithstanding the
foregoing, any employee who immediately prior to August 28, 2002 (i) was an
eligible employee under the Viacom Excess 401(k) Plan and (ii) was a Reporting
Employee, became an Eligible Employee under this Plan effective August 28, 2002.

        2.8    Employer.    The term "Employer" means the Company and any
affiliate or subsidiary that adopts the Plan on behalf of its Eligible
Employees.

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        2.9    Employer Match.    The term "Employer Match" means the amounts
credited to a Participant's Account with respect to a Participant's Excess
Salary Reduction Contributions, calculated using the rate of matching
contributions under the Viacom 401(k) Plan in effect at the time such Excess
Salary Reduction Contributions are made.

        2.10    Excess Salary Reduction Contributions.    The term "Excess
Salary Reduction Contributions" means the portion of a Participant's
Compensation earned during a Plan Year (after such Participant has reached any
Limitation) that he elects to defer under the terms of this Plan.

        2.11    Investment Options.    The term "Investment Options" means the
investment funds available to participants in the Viacom 401(k) Plan, excluding
the Self-Directed Brokerage Account.

        2.12    Joint Payment Option.    The term "Joint Payment Option" means,
in accordance with Section 5.2, (i) any payment option election made by a
Participant in effect in the Viacom Excess 401(k) Plan immediately prior to
August 28, 2002, and (ii) any payment option election made on or after
August 28, 2002. A Joint Payment Option shall apply to all amounts credited to
the Participant's Account in this Plan, his account in the Viacom Excess 401(k)
Plan and his account in the Viacom Bonus Deferral Plan for Designated Senior
Executives.

        2.13    Limitation.    The term "Limitation" means the limitation on
contributions to defined contribution plans under Section 415(c), on
compensation taken into account under Section 401(a)(17), or on elective
deferrals under Section 401(k)(3) and Section 402(g) of the Internal Revenue
Code of 1986.

        2.14    Participant.    The term "Participant" means an Eligible
Employee who elects to have Excess Salary Reduction Contributions made to the
Plan.

        2.15    Plan.    The term "Plan" means the Viacom Excess 401(k) Plan for
Designated Senior Executives as set forth herein, as amended from time to time.

Section 3.    Participation.

        3.1    Designation of Eligible Employees.    Beginning August 28, 2002,
each month the Committee will designate in its sole discretion those employees
who satisfy the terms of paragraph 2.7 as eligible to participate in the Plan.

        3.2    Election to Participate.    An Eligible Employee must elect to
participate in the Plan. An Eligible Employee may elect, at any time after
becoming eligible, to begin participation and to commence making Excess Salary
Reduction Contributions during the Plan Year by filing an election with the
Committee in accordance with this Section 3 and the rules and regulations
established by the Committee. Such election will be effective on a prospective
basis beginning with the payroll period that occurs as soon as administratively
practicable following receipt of the election by the Committee.

        3.3    Amendment or Suspension of Election.    Participants may change
(including, suspend) their existing Excess Salary Reduction Contribution
election under this Plan during the Plan Year by filing a new election in
accordance with the prescribed administrative guidelines. Such new election will
be effective on a prospective basis beginning with the payroll period that
occurs as soon as administratively practicable following receipt of the election
by the Committee. A Participant will not be permitted to make up suspended
Excess Salary Reduction Contributions, and during any period in which a
Participant's Excess Salary Reduction Contributions are suspended, the Employer
Match to the Plan will also be suspended.

        3.4    Amount of Elections.    Each election filed by an Eligible
Employee must specify the amount of Excess Salary Reduction Contributions in a
whole percentage between 1% and 15% of the Participants' Compensation, excluding
any Bonus. Except as described otherwise in this Section 3.4, no Eligible
Employee shall be permitted during any Plan Year to make Excess Salary Reduction
Contributions at a rate that exceeds the rate of his Before-Tax Contributions to
the Viacom 401(k) Plan

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as in effect immediately preceding the time that the Eligible Employee actually
commences Excess Salary Reduction Contributions to this Plan for that particular
Plan Year. Notwithstanding the foregoing, for the Plan Year ending December 31,
2002, any Eligible Employee who on August 28, 2002 had in effect an Excess
Salary Reduction Contribution election that exceeded the rate of his Before-Tax
Contributions to the Viacom 401(k) Plan as in effect immediately preceding the
time that the Eligible Employee actually commences Excess Salary Reduction
Contributions to this Plan shall be permitted to continue that Excess Salary
Deferral Contribution election for the remainder of such Plan Year.

Section 4.    Employer Match.

        An Employer Match will be credited approximately every two weeks to a
Participant's Account with respect to the eligible portion of Excess Salary
Reduction Contributions of such Participant. The eligible portion of a
Participant's Excess Salary Reduction Contributions shall be limited to 5% of
each contribution. The eligible portion of a Participant's Excess Salary
Reduction Contributions shall be based on Compensation up to an annual maximum
amount of $750,000.

Section 5.    Individual Account.

        5.1    Creation of Accounts.    The Company will maintain an Account in
the name of each Participant. Each Participant's Account will be credited with
the amount of the Participant's Excess Salary Reduction Contributions, and
Employer Match, if any, made in all Plan Years.

        5.2    Joint Payment Option Election.    

        (a)    Any Joint Payment Option defined in Section 2.12(i) shall
continue to apply until changed by the Participant in accordance with this
Section 5.

        (b)    Any Eligible Employee who first becomes a Participant on or after
August 28, 2002 and who has not elected a Joint Payment Option under Section 4.2
of the Viacom Bonus Deferral Plan, Section 4.2 of the Viacom Bonus Deferral Plan
for Designated Senior Executives or under Section 5.2 of the Viacom Excess
401(k) Plan shall elect a Joint Payment Option at the same time that the
Participant files his initial election to commence participation in the Plan
pursuant to Section 3.2. Such Joint Payment Option shall continue to apply until
changed by the Participant in accordance with this Section 5

        (c)    A Participant may elect to receive his entire Account under
either of the following Joint Payment Options: (1) a single lump sum; or,
(2) annual payments over a period of two, three, four or five years on or about
January 31 beginning in the calendar year immediately following the end of the
Plan Year in which the Participant terminates employment. If no Joint Payment
Option election is made in accordance with the terms of the Plan, the Viacom
Excess 401(k) Plan or the Viacom Deferred Bonus Plan for Designated Senior
Executives, a Participant shall be deemed to have elected to receive his Account
in a single lump sum on or about January 31 of the calendar year immediately
following the end of the Plan Year in which the Participant terminates
employment. If a Participant makes a Joint Payment Option election to receive
payments in a single lump sum, such lump sum shall be payable on or about
January 31 of the calendar year immediately following the end of the Plan Year
in which the Participant terminates employment, unless the Participant elects to
be paid on or about January 31 of the 2nd, 3rd, 4th or 5th calendar year
following the year in which the Participant terminates employment. If a
Participant elects to receive annual payments over a period of two or more
years, such annual payments shall be made in substantially equal annual
payments, unless the Participant designates at the time of making his Joint
Payment Option election a specific percentage of his Account to be distributed
in each year. All specified percentages must be a whole multiple of 10% and the
total of all designated percentages must be equal to 100%.

        Example 1:    If a Participant elects (or is deemed to elect) a Payment
Option that provides for a lump sum payment and terminates employment in 2002,
such lump sum shall be paid on or about

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January 31, 2003. A Participant alternatively could designate January 31 of
2004, 2005, 2006 or 2007 in which to receive his lump sum.

        Example 2:    If a Participant elects a Payment Option that provides for
annual installments over a period of four years and terminates employment in
2002, each installment paid on or about January 31, 2003 through 2006 will be
comprised of approximately 25% of the Participant's Account as of the
Participant's date of termination. A Participant alternatively could designate
10% of his Account to be distributed in January, 2003, 20% in January, 2004, 30%
in January, 2005 and 40% in January 2006; or, any other combination of
percentages that totals 100%.

        (d)    A Participant may change his Joint Payment Option no more than
three times over the course of his employment with the Company or an Affiliate.
A Participant may change an existing Joint Payment Option only one time in any
calendar year. Any change of a Participant's existing Joint Payment Option
election made less than six months prior to the Participant's termination of
employment for any reason shall be null and void and the Participant's last
valid Payment Option shall remain in effect.

        a.    Investments.    

        (a)    All Excess Salary Reduction Contributions, Excess Bonus Deferral
Contributions and Employer Match, if any, will be credited through December 31st
of the calendar year in which the Participant terminates employment with an
amount equal to such amount which would have been earned had such contributions
been invested in the same Investment Options and in the same proportion as the
Participant may elect, from time to time, to have his Salary Reduction
Contributions and Matching Employer Contributions invested under the Viacom
401(k) Plan; or if no such election has been made, in the PRIMCO Stable Value
Fund (or any successor fund).

        (b)    If a Participant elects (or is deemed to elect) a single lump sum
Joint Payment Option payable in the first calendar year following the calendar
year in which the Participant terminates employment, no additional adjustments
will be made to the Participant's Account after December 31st of the calendar
year in which the Participant terminates employment. If a Participant elects a
single lump sum Joint Payment Option payable in the second, third, fourth or
fifth calendar year following the calendar year in which the Participant
terminates employment, the Participant's Account shall be credited with earnings
based on the rate of return in the PRIMCO Stable Value Fund (or any successor
fund) beginning January 1st of the calendar year following the year in which the
Participant terminates employment and continuing through December 31st of the
calendar year immediately preceding the calendar year in which the single lump
sum is paid.

        (c)    If a Participant elects annual payments, no additional
adjustments will be made to any amount payable in the first calendar year
following the year in which the Participant terminates employment. For any
annual payments made in the second, third, fourth or fifth year following the
calendar year in which the Participant terminates employment, the Participant's
Account shall be credited with earnings based on the rate of return in the
PRIMCO Stable Value Fund (or any successor fund) beginning January 1st of the
calendar year following the year in which the Participant terminates employment
and continuing through December 31st of the calendar year immediately preceding
the calendar year in which each payment is made.

        (d)    No provision of this Plan shall require the Company or the
Employer to actually invest any amounts in any fund or in any other investment
vehicle.

        5.4    Account Statements.    Each Participant will be given, at least
annually, a statement showing (i) the amount of Contributions, (ii) the amount
of Employer Match, if any, made with respect to his Account for such Plan Year,
and (iii) the balance of the Participant's Account after crediting Investments.

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Section 6.    Payment.

        A Participant (or a Participant's beneficiary) shall be paid the balance
in his Account following termination of employment in accordance with the Joint
Payment Option in effect with respect to the Participant.

Section 7.    Nature of Interest of Participant.

        Participation in this Plan will not create, in favor of any Participant,
any right or lien in or against any of the assets of the Company or any
Employer, and all amounts of Compensation deferred hereunder shall at all times
remain an unrestricted asset of the Company or the Employer. A Participant's
rights to benefits payable under the Plan are not subject in any manner to
anticipation, alienation, sale, transfer, assignment, pledge, or encumbrance.
All payments hereunder shall be paid in cash from the general funds of the
Company or applicable Employer and no special or separate fund shall be
established and no other segregation of assets shall be made to assure the
payment of benefits hereunder. Nothing contained in this Plan, and no action
taken pursuant to its provisions, shall create or be construed to create a trust
of any kind, or a fiduciary relationship, between any Employer and a Participant
or any other person, and the Company's and each Employer's promise to pay
benefits hereunder shall at all times remain unfunded as to the Participant.

Section 8.    Hardship Distributions and Deferral Revocations.

        A Participant may request the Committee to accelerate distribution of
all or any part of the value of his Account solely for the purpose of
alleviating an immediate financial emergency. For purposes of the Plan, such an
immediate financial emergency shall mean an unanticipated emergency that is
caused by an event beyond the control of the Participant and which would result
in severe financial hardship to the Participant if early distribution were not
permitted. The Committee may request that the Participant provide certifications
and other evidence of qualification for such emergency hardship distribution as
it determines appropriate. The decision of the Committee with respect to the
grant or denial of all or any part of such request shall be in the sole
discretion of the Committee, whether or not the Participant demonstrates an
immediate financial emergency exists, and shall be final and binding and not
subject to review.

Section 9. Beneficiary Designation.

        A Participant's beneficiary designation for this Plan will automatically
be the same as the Participant's beneficiary designation recognized under the
Viacom 401(k) Plan, unless a separate Designation of Beneficiary Form for this
Plan has been properly filed.

Section 10.    Administration.

        10.1    Committee.    This Plan will be administered by the Committee,
the members of which will be selected by the Board of Directors.

        10.2    Powers of the Committee.    The Committee's powers will include,
but will not be limited to, the power

(i)to determine who are Eligible Employees for purposes of participation in the
Plan, (ii)to interpret the terms and provisions of the Plan and to determine any
and all questions arising under the Plan, including without limitation, the
right to remedy possible ambiguities, inconsistencies, or omissions by a general
rule or particular decision, (iii)to adopt rules consistent with the Plan, and.
(iv)to approve certain amendments to the Plan.

        10.3    Claims Procedure.    The Committee shall have the exclusive
right to interpret the Plan and to decide any and all matters arising
thereunder. In the event of a claim by a Participant as to the

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amount of any distribution or method of payment under the Plan, within 90 days
of the filing of such claim, unless special circumstances require an extension
of such period, such person will be given notice in writing of any denial, which
notice will set forth the reason for the denial, the Plan provisions on which
the denial is based, an explanation of what other material or information, if
any, is needed to perfect the claim, and an explanation of the claims review
procedure. The Participant may request a review of such denial within 60 days of
the date of receipt of such denial by filing notice in writing with the
Committee. The Participant will have the right to review pertinent Plan
documents and to submit issues and comments in writing. The Committee will
respond in writing to a request for review within 60 days of receiving it,
unless special circumstances require an extension of such period. The Committee,
at its discretion, may request a meeting to clarify any matters deemed
appropriate.

        10.4    Finality of Committee Determinations.    Determinations by the
Committee and any interpretation, rule, or decision adopted by the Committee
under the Plan or in carrying out or administering the Plan shall be final and
binding for all purposes and upon all interested persons, their heirs, and
personal representatives.

        10.5    Severability.    If a provision of the Plan shall be held
illegal or invalid, the illegality or invalidity shall not affect the remaining
parts of the Plan, and the Plan shall be construed and enforced as if the
illegal or invalid provision had not been included in the Plan.

        10.6    Governing Law.    The provisions of the Plan shall be governed
by and construed in accordance with the laws of the State of New York, to the
extent not preempted by the laws of the United States.

        10.7    Gender.    Wherein used herein, words in the masculine form
shall be deemed to refer to females as well as males.

Section 11.    No Employment Rights.

        No provisions of the Plan or any action taken by the Company, the Board
of Directors, or the Committee shall give any person any right to be retained in
the employ of any Employer, and the right and power of the Company to dismiss or
discharge any Participant is specifically reserved.

Section 12.    Amendment, Suspension, and Termination.

        The Retirement Committee shall have the right to amend the Plan at any
time, unless provided otherwise in the Company's governing documents. The Board
of Directors shall have the right to suspend or terminate the Plan at any time.
No amendment, suspension or termination shall, without the consent of a
Participant, adversely affect such Participant's rights in his account. In the
event the Plan is terminated, the Committee shall continue to administer the
Plan in accordance with the relevant provisions thereof.

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