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                                                                    EXHIBIT 10.4

THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED,
OR ANY APPLICABLE STATE SECURITIES LAWS, AND NO OFFER, TRANSFER OR ASSIGNMENT OF
THIS NOTE MAY BE MADE IN THE ABSENCE OF SUCH REGISTRATIONS OR UNLESS EXEMPTIONS
FROM SUCH REGISTRATIONS ARE AVAILABLE.

                                 PROMISSORY NOTE

$ 3,748,800                                                 Dated: April 1, 2000

         FOR VALUE RECEIVED, the undersigned Horseshoe Gaming Holding Corp., a
Delaware corporation (the "Maker"), hereby promises to pay to the order of G.A.
Robinson III, a Tennessee resident, or his successors and assigns ("Holder"), at
the address specified in Section 7 herein, or at such other place as Holder may
direct, the principal amount of Three Million Seven Hundred and Forty-Eight
Thousand and Eight Hundred Dollars ($3,748,800), plus interest, as provided
herein.

         1. PURCHASE AGREEMENT. This Note is issued pursuant to the terms and
conditions of a Purchase Agreement dated as of the date hereof (the "Purchase
Agreement"), between the Company and the Holder, as consideration for the
repurchase by the Company of 100 shares of Holder's ownership interest in the
Company (the "Ownership Interest").

         2. PRINCIPAL PAYMENT MATURITY. The outstanding principal balance
hereunder shall be payable, together with all accrued but unpaid interest, shall
be payable on April 30, 2005 ("Maturity Date"); provided, however, from time to
time, Make shall prepay the maximum amount allowed, after making all payments on
account of all other required installments to repurchase ownership interest or
debt associated with the prior repurchase of equity of Maker or any of its
affiliates or subsidiaries, pursuant to the terms of any of its trust
indentures, notes, guarantees or other documents providing primary institutional
financing to Maker or any of its subsidiaries or affiliates (collectively, the
"Financing Documents"). Notwithstanding anything contained herein to the
contrary, Maker shall not be required to make prepayments, if, after satisfying
all other required installments to repurchase ownership interest or debt
associated with the prior repurchase of equity of Maker or any of its affiliates
or subsidiaries the anticipated payment to Holder would cause Make to be in
default under the Financing Documents or would cause the Chief Financial Officer
of Maker to reasonably foresee a default pursuant to the Financing Documents. In
all events, Make shall pay all sums due Holder under this Note on or before the
Maturity Date.

         3. INTEREST. The Company promises to pay simple interest on the
outstanding principal amount of this Note at a rate equal to 9% per annum (the
"Interest Rate") from April 1, 2000 until the maturity date of this or the
earlier acceleration of this Note


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pursuant to Section 6 of this Note, when all accrued interest shall be
immediately due and payable. Interest shall be computed on the basis of a
360-day year of twelve 30-day months. Subject to the terms of the Financing
Documents and the various agreements entered into prior to the date hereof to
repurchase the interests of various former employees and owners of the Company
(the "Repurchase Agreements"), which, among other things, do not permit the
Company to make principal payments on the repurchase of the Ownership Interest
prior to the repayment in full of amounts due under the Repurchase Agreements,
the Company shall pay accrued interest semiannually on June 30 and December 31
of each year, beginning on June 30, 2000. To the extent that the Company is not
permitted to make interest payments under the Financing Documents or the
Repurchase Agreements, interest shall accrue and be compounded at the Interest
Rate until the earlier of the date such interest is paid, the maturity date of
this Note or the earlier acceleration of this Note pursuant to Section 6 of this
Note.

         The principal and any unpaid installment of interest, as evidenced by
this Note, shall bear interest from the date of maturity (whether by demand,
acceleration or otherwise) until this Note is paid in full at 11% per annum.

         In the event any principal or interest due hereunder shall not be paid
when due, and such default shall continue for a period of ten (10) days from the
date such payment shall have been due and payable (without regard to any cure or
grace period), including principal and accrued interest becoming due by reason
of acceleration of the entire unpaid balance of the Note, Maker agrees to pay to
the Holder a late fee equal to 1% of the amount overdue; provided that such late
charge shall be reduced by the amount by which such charge, together with the
other sums payable under this Note constituting interest, exceeds the maximum
rate Holder is permitted to charge under applicable law.

         4. PREPAYMENT. Maker may prepay all or any portion of the unpaid
balance of the principal hereof, without premium or penalty. All sums received
in prepayment shall first be applied in payment of accrued but unpaid interest,
if any, and the excess shall be applied to payment of the principal due and
payable under Section 1 of this Note.

         5. METHOD OF PAYMENT. Both principal and interest shall be paid by
Maker in lawful currency of the United States of America to Holder at the
address of Holder specified in Section 7 of this Note or at such other place as
Holder shall direct.

         6. EVENTS OF DEFAULT. Each of the following constitutes an "Event of
Default" hereunder:

                  1. If after providing five (5) days written notice to Maker,
if principal of or interest on this Note is not paid within ten (10) days after
the Due Date thereof.

                  2. If after providing five (5) days written notice to Maker,
if the Maker is insolvent or generally fails to pay, or admits in writing the
Maker's inability to pay debts as they become due; or the Maker applies for,
consents to or acquiesces in the appointment of a trustee, receiver or other
custodian for the benefit of creditors; or, in the


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absence of such application, consent or acquiescence, a trustee, receiver or
other custodian is appointed for the Maker or for a substantial part of the
property or assets of the Maker and is not discharged within sixty (60) days; or
any bankruptcy, reorganization, debt arrangement, or other case or proceeding
under any bankruptcy or insolvency law, or any dissolution or liquidation
proceeding, is commenced in respect of the Maker and if such case or proceeding
is not commenced by the Maker it is consented to or acquiesced in by the Maker
or is such case or proceeding is not vacated, stayed or dismissed within sixty
(60) days of such commencement.

         7. REMEDIES UPON AN EVENT OF DEFAULT. If an Event of Default shall
occur, then Holder may, at his option, exercise any one or more of the following
rights and remedies:

                  1. The Holder may declare the entire unpaid amount of this
Note to be immediately due and payable without presentment, demand, protest or
notice of any kind, all of which the Maker expressly waives;

                  2. Holder shall be entitled to all of the rights and remedies
in accordance with, and as provided by, the terms of this Note; and

                  3. Holder may exercise from time to time any rights and
remedies available to it under all applicable laws, including, without
limitation, the Nevada Uniform Commercial Code.

In addition, the Holder shall be entitled to recover from the Maker all costs
and expenses, including reasonable attorneys' fees and court costs, incurred in
enforcing his rights hereunder. The rights and remedies of Holder stated herein
are cumulative to and not exclusive of any rights or remedies otherwise
available to Holder.

         8. NOTICES. All notices, request, demands and other communications
under this Note shall be in writing and shall be deemed to have been duly given
on the date received if delivered personally to the party to whom notice is to
be given, or on the date of receipt if mailed by registered or certified mail,
return receipt requested, postage prepaid, to the following addresses:

If to the Maker, to:                           With a copy to:

         Horseshoe Gaming Holding Corp.        Dominic F. Polizzotto, Esq.
         P.O. Box 2789                         Ice, Miller, Donadio & Ryan
         Joliet, IL 60634-2789                 One American Square, Box 82001
         Attn: Chief Financial Officer         Indianapolis, IN 46282-0002

If to the Holder, to:

         Mr. G.A. Robinson III                 Lawson F. Apperson, Esq.
         100 North Main Street                 Wyatt, Tarrant & Combs
         Suite 3100                            P.O. Box 775000
         Memphis, TN 38103                     Memphis, Tennessee 38177-5000


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         9. MISCELLANEOUS.

         (a) This Note shall in all respects be governed by and construed in
accordance with the laws of the State of Illinois without regard to conflicts of
law principles.

         (b) If more than one person shall be a Holder under this Note, all
rights of Holder under this Note and all determinations and actions of Holder
under this Note shall be exercised, made, taken by or only with the consent of
the Holders of a majority interest of the then outstanding principal amount of
this Note.

         (c) Holder shall not (by act, delay, omission or otherwise) be deemed
to have waived any of its rights or remedies hereunder, or any provision hereof,
unless such waiver is in writing signed by Holder, and any such waiver shall be
effective only to the extent specifically set forth therein; and a waiver by
Holder of any right or remedy under this Note on any one occasion shall not be
construed as a bar to or waiver of any such right or remedy which Holder would
otherwise have has on any occasion. The Maker and any endorsers hereof waive
protest, demand, presentment, and notice of dishonor.

         (d) Wherever possible, each provision of this Note which as been
prohibited by or hold invalid under applicable law shall be ineffective to the
extent of such prohibition or invalidity, but such prohibition or invalidity
shall not invalidate the remainder of such provision or the remaining provisions
of this Note.

         (e) Wherever in this Note reference is made to Maker or Holder, such
reference shall be deemed to include, as applicable, a reference to their
respective successors and assigns, legatees, heirs, executors, administrators
and legal representatives, as applicable, and, in the case of Holder, any future
holder of this Note, in any case as permitted by this Note. The provisions of
this Note shall be binding upon and shall inure to the benefit of such
successors, assigns, holders, legatees, heirs, executors, administrators and
legal representatives, as applicable.

         IN WITNESS WHEREOF, Maker has executed, acknowledged, sealed and
delivered this Note as of the day and year first above written.

                                   Horseshoe Gaming Holding Corporation


                                   By: /s/ Kirk Saylor
                                       -----------------------------------------
                                       Kirk Saylor, Chief Financial Officer