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                                                                     EXHIBIT 4.1



        THIRD SUPPLEMENTAL INDENTURE, dated as of August 21, 1998, among ACME
TELEVISION, LLC, a Delaware limited liability company (the "Company"), and ACME
FINANCE CORPORATION, a Delaware corporation ("Finance" and, together with the
Company, jointly and severally, the "Issuers"), the Guarantors (as defined in
the Indenture (as defined herein) and referred to herein as the "Original
Guarantors"), the Additional Guarantors (as defined in the First Supplemental
Indenture (as defined herein) and referred to herein as the "Additional
Guarantors"), the Successor Guarantors (as defined in the First Supplemental
Indenture and referred to herein as the "Successor Guarantors"), the Additional
Missouri Guarantors (as defined in the Second Supplemental Indenture (as defined
herein) and referred to herein as the "Additional Missouri Guarantors") and ACME
Television of Florida, LLC, a Delaware limited liability company ("Television
Florida"), and ACME Television Licenses of Florida, LLC, a Delaware limited
liability company ("Licenses Florida"), (each a "Florida Guarantor" and,
together the "Florida Guarantors," and, together with the Additional Missouri
Guarantors, the Additional Guarantors, the Successor Guarantors and the Original
Guarantors, the "Guarantors"), and WILMINGTON TRUST COMPANY (the "Trustee"), as
Trustee under the Indenture.

            WHEREAS, the Issuers, the Original Guarantors and the Trustee have
previously entered into an Indenture dated as of September 30, 1997 (the
"Indenture") relating to the Issuers' 10 7/8% Senior Discount Notes due 2004
(the "Notes"); the Issuers, the Original Guarantors, the Additional Guarantors,
the Successor Guarantors and the Trustee have previously entered into a First
Supplemental Indenture dated as of February 11, 1998 (the "First Supplemental
Indenture") which amended the Indenture to provide for the guarantees of the
Additional Guarantors and the Successor Guarantors; and the Issuers, the
Original Guarantors, the Additional Guarantors, the Successor Guarantors, the
Additional Missouri Guarantors and the Trustee have previously entered into a
Second Supplemental Indenture dated as of March 13, 1998 (the "Second
Supplemental Indenture") which amended the Indenture to provide for the
guarantees of the Additional Missouri Guarantors;

            WHEREAS, with respect to the Florida Guarantors, Section 9.01 of the
Indenture provides that the Issuers, the Original Guarantors and the Trustee
may, without the written consent of the holders of the outstanding Notes, amend
the Indenture as provided therein to provide for the acquisition of subsidiaries
by the Issuers;

            WHEREAS, the Board of Directors or the Majority Member of each of
the Issuers, and the Original Guarantors have consented to this Third
Supplemental Indenture; and

            WHEREAS, all acts and things prescribed by the Certificate of
Formation and the Operating Agreement (each as now in effect) of each of
Licenses Florida and Television Florida necessary to make this Third
Supplemental Indenture a valid instrument legally binding on each of the Florida
Guarantors for the purposes herein expressed, in accordance with its terms, have
been duly done and performed;

            NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Issuers, the Original Guarantors, the Additional Guarantors, the Successor
Guarantors, the Additional Missouri Guarantors, the



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Florida Guarantors and the Trustee hereby agree for the benefit of each other
and the equal and ratable benefit of the holders of the Notes as follows:


        1. Additional Guarantors. As of the date hereof and pursuant to this
Third Supplemental Indenture, ACME Television of Florida, LLC, a Delaware
limited liability company, and ACME Television Licenses of Florida, LLC, a
Delaware limited liability company, each hereby becomes a Guarantor under the
Indenture in accordance with the terms and conditions of the Indenture and shall
each assume all rights and obligations of a Guarantor thereunder.

        2. Compliance with and Fulfillment of Condition of Article IX. Each
Florida Guarantor's execution and delivery of this Third Supplemental Indenture
and the respective Guarantee (along with such documentation relating thereto as
the Trustee shall require, including, without limitation, an Opinion of Counsel
as to the enforceability of each such Guarantee and the Third Supplemental
Indenture and an Officer's Certificate from each entity) fulfills its
requirements under Section 9.01 of the Indenture.

        3. Construction. For all purposes of this Third Supplemental Indenture,
except as otherwise herein expressly provided or unless the context otherwise
requires: (i) the terms and expressions used herein shall have the same meanings
as corresponding terms and expressions used in the Indenture; and (ii) the words
"herein," "hereof" and "hereby" and other words of similar import used in this
Third Supplemental Indenture refer to this Third Supplemental Indenture as a
whole and not to any particular Section hereof.

        4. Trustee Acceptance. The Trustee accepts the amendment of the
Indenture effected by this Third Supplemental Indenture, as hereby amended, but
only upon the terms and conditions set forth in the Indenture, as hereby
amended, including the terms and provisions defining and limiting the
liabilities and responsibilities of the Trustee in the performance of its duties
and obligations under the Indenture, as hereby amended. Without limiting the
generality of the foregoing, the Trustee has no responsibility for the
correctness of the recitals of fact herein contained which shall be taken as the
statements of each of the Issuers and the Guarantors, respectively, and makes no
representations as to the validity or enforceability against any of the Issuers
and the Guarantors.

        5. Indenture Ratified. Except as expressly amended hereby, the Indenture
is in all respects ratified and confirmed and all the terms, conditions and
provisions thereof shall remain in full force and effect.

        6. Holders Bound. This Third Supplemental Indenture shall form a part of
the Indenture for all purposes, and every holder of the Notes heretofore and
hereafter authenticated and delivered shall be bound hereby.

        7. Successors and Assigns. This Third Supplemental Indenture shall be
binding upon and inure to the benefit of the parties hereto and their respective
successors and assigns.



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        8. Counterparts. 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, and all of such counterparts shall together constitute one and the
same instrument.


        9. Governing Law. This Third Supplemental Indenture and the Guarantees
hereunder shall be governed by and construed in accordance with the internal
laws of the State of New York without giving effect to principles of conflicts
of laws.


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        IN WITNESS WHEREOF, the Issuers, the Guarantors and the Trustee have
caused this Third Supplemental Indenture to be duly executed as of the date
first above written.

ISSUERS:

ACME TELEVISION, LLC
ACME FINANCE CORPORATION


                                             ATTEST:


By: /s/ Douglas Gealy                        By: /s/ Thomas Allen
   -------------------------------              -------------------------------
    Douglas Gealy                                Thomas Allen
    President and Chief Operating                Executive Vice-President and
       Officer                                      Chief Financial Officer


GUARANTORS:

FLORIDA GUARANTORS:

   ACME TELEVISION OF FLORIDA, LLC
   ACME TELEVISION LICENSES OF FLORIDA, LLC


                                             ATTEST:


By: /s/ Douglas Gealy                        By: /s/ Thomas Allen
   -------------------------------              -------------------------------
    Douglas Gealy                                Thomas Allen
    President and Chief Operating                Executive Vice-President and
       Officer                                      Chief Financial Officer

(for each of the above-listed Florida Guarantors)



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ADDITIONAL MISSOURI GUARANTORS:

   ACME TELEVISION OF MISSOURI, INC.
   ACME TELEVISION LICENSES OF MISSOURI, LLC


                                             ATTEST:


By: /s/ Douglas Gealy                        By: /s/ Thomas Allen
   -------------------------------              -------------------------------
    Douglas Gealy                                Thomas Allen
    President and Chief Operating                Executive Vice-President and
       Officer                                      Chief Financial Officer

(for each of the above-listed Additional Missouri Guarantors)

SUCCESSOR GUARANTORS:

   ACME TELEVISION HOLDINGS OF OREGON, LLC
   ACME TELEVISION HOLDINGS OF TENNESSEE, LLC
   ACME TELEVISION LICENSES OF OREGON, LLC
   ACME TELEVISION LICENSES OF TENNESSEE, LLC
   ACME TELEVISION OF TENNESSEE, LLC
   ACME TELEVISION OF OREGON, LLC


                                             ATTEST:


By: /s/ Douglas Gealy                        By: /s/ Thomas Allen
   -------------------------------              -------------------------------
    Douglas Gealy                                Thomas Allen
    President and Chief Operating                Executive Vice-President and
       Officer                                      Chief Financial Officer

(for each of the above-listed Successor Guarantors)



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ADDITIONAL GUARANTORS:

   ACME TELEVISION LICENSES OF UTAH, LLC
   ACME TELEVISION OF NEW MEXICO, LLC
   ACME TELEVISION OF UTAH, LLC

                                             ATTEST:


By: /s/ Douglas Gealy                     By: /s/ Thomas Allen
   -------------------------------           -------------------------------
    Douglas Gealy                             Thomas Allen
    President and Chief Operating             Executive Vice-President and
       Officer                                   Chief Financial Officer

(for each of the above-listed Additional Guarantors)

ORIGINAL GUARANTORS:

   ACME TELEVISION LICENSES OF MISSOURI, INC.
   ACME TELEVISION HOLDINGS OF UTAH, LLC
   ACME TELEVISION HOLDINGS OF NEW MEXICO, LLC
   ACME TELEVISION LICENSES OF NEW MEXICO, LLC
   ACME SUBSIDIARY HOLDINGS III, LLC

                                          ATTEST:


By: /s/ Douglas Gealy                     By: /s/ Thomas Allen
   -------------------------------           -------------------------------
    Douglas Gealy                             Thomas Allen
    President and Chief Operating             Executive Vice-President and
       Officer                                   Chief Financial Officer

(for each of the above-listed Original Guarantors)


WILMINGTON TRUST COMPANY


                                          ATTEST:


By: /s/ Bruce L. Bisson                   By: /s/ Charlotte Paglia
   -------------------------------           -------------------------------
    Name:   Bruce L. Bisson                   Name:   Charlotte Paglia
    Title:  Vice President                    Title:  Financial Services Officer