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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                    FORM 10-K

                                  ANNUAL REPORT

                       Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934



           For the fiscal year ended:           Commission file number:
              December 31, 2004                        001-32201

                          MERRILL LYNCH DEPOSITOR, INC.
                    (ON BEHALF OF PPLUS TRUST SERIES DCNA-1)
             (Exact name of registrant as specified in its charter)

               DELAWARE                                 13-3891329
            (State or other                         (I. R. S. Employer
            jurisdiction of                         Identification No.)
            incorporation)




        WORLD FINANCIAL CENTER,                            10080
          NEW YORK, NEW YORK                            (Zip Code)
         (Address of principal
          executive offices)

                       ----------------------------------


       Registrant's telephone number, including area code: (212) 449-1000

Securities registered pursuant to Section 12(b) of the Act:

PPLUS Trust Certificates Series DCNA-1 listed on The New York Stock Exchange.

Securities registered pursuant to Section 12(g) of the Act:

Not Applicable.

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was to
file such reports), and (2) has been subject to such filing requirements for the
past 90 days.

                                 Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this form 10-K or any amendment to this
form 10-K.

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Act).

                                 Yes [ ] No [X]

State the aggregate market value of the voting and non-voting common equity held
by non-affiliates of the registrant. The aggregate market value shall be
computed by reference to the price at which the common equity was sold, or the
average bid and asked prices of such common equity, as of the last business day
of the registrant's most recently completed second fiscal quarter.

Not Applicable.

Indicate the number of shares outstanding for each of the registrant's class of
common stock, as of the latest practicable date.

Not Applicable.
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                       DOCUMENTS INCORPORATED BY REFERENCE

None.


         PART I

         ITEM 1.        BUSINESS

                        For information with respect to the underlying
                        securities held by PPLUS Trust Series DCNA-1, please
                        refer to DaimlerChrysler AG's (Commission file number
                        001-14561) periodic reports, including reports on Form
                        20-F and Form 6-K, and other information on file with
                        the Securities and Exchange Commission (the "SEC"). You
                        can read and copy these reports and other information at
                        the public reference facilities maintained by the SEC at
                        Room 1024, 450 Fifth Street, NW, Washington, D.C. 20549.
                        You may obtain copies of this material for a fee by
                        writing to the SEC's Public Reference Section of the SEC
                        at 450 Fifth Street, NW, Washington, D.C. 20549. You may
                        obtain information about the operation of the Public
                        Reference Room by calling the SEC at 1-800-SEC-0330. You
                        can also access some of this information electronically
                        by means of the SEC's website on the Internet at
                        http://www.sec.gov, which contains reports, proxy and
                        information statements and other information that the
                        underlying securities guarantor and the underlying
                        securities issuer has filed electronically with the SEC.

                        Although we have no reason to believe the information
                        concerning the underlying securities guarantee and
                        underlying securities or the underlying securities
                        guarantor and the underlying securities issuer contained
                        in the underlying securities guarantor's Exchange Act
                        reports is not reliable, neither the depositor nor the
                        trustee participated in the preparation of such
                        documents or made any due diligence inquiry with respect
                        to the information provided therein. No investigation
                        with respect to the underlying securities guarantor and
                        underlying securities issuer (including, without
                        limitation, no investigation as to its financial
                        condition or creditworthiness) or of the underlying
                        securities and underlying securities guarantee has been
                        made. You should obtain and evaluate the same
                        information concerning the underlying securities issuer
                        and the underlying securities guarantor as you would
                        obtain and evaluate if your investment were directly in
                        the underlying securities or in other securities issued
                        by the underlying securities issuer or the underlying
                        securities guarantor. There can be no assurance that
                        events affecting the underlying securities and
                        underlying securities guarantee or the underlying
                        securities issuer and underlying securities guarantor
                        have not occurred or have not yet been publicly
                        disclosed which would affect the accuracy or
                        completeness of the publicly available documents
                        described above.

                        PPLUS Trust Series DCNA-1 was established on May 28,
                        2004 pursuant to the PPLUS Trust Certificates Series
                        DCNA-1 Series Supplement dated May 28, 2004 as attached
                        as an exhibit to the Registrant's current report on Form
                        8-K filed with the Securities and Exchange Commission on
                        June 2, 2004.

         ITEM 2.        PROPERTIES

                        None.

         ITEM 3.        LEGAL PROCEEDINGS

                        None.

         ITEM 4.        SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

                        None.

                                       2
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         PART II

         ITEM 5.        MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED
                        STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY
                        SECURITIES

                        The Trust Certificates issued by PPLUS Trust Series
                        DCNA-1 are represented by one or more physical
                        certificates registered in the name of Cede & Co., the
                        nominee of the Depository Trust Company. The Trust
                        Certificates are listed on the New York Stock Exchange.

         ITEM 6.        SELECTED FINANCIAL DATA

                        Not Applicable.

         ITEM 7.        MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                        CONDITION AND RESULTS OF OPERATIONS

                        Not Applicable.

         ITEM 7A.       QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET
                        RISK

                        Not Applicable.

         ITEM 8.        FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                        Not Applicable.

         ITEM 9.        CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON
                        ACCOUNTING AND FINANCIAL DISCLOSURE

                        None.

         ITEM 9A.       CONTROLS AND PROCEDURES

                        The Registrant has procedures so as to provide
                        reasonable assurance that its future Exchange Act
                        filings will be filed within the applicable time
                        periods.

         ITEM 9B.       OTHER INFORMATION

                        None.


                                       3
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         PART III

         ITEM 10.       DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

                        Not Applicable.

         ITEM 11.       EXECUTIVE COMPENSATION

                        Not Applicable.

         ITEM 12.       SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND
                        MANAGEMENT AND RELATED STOCKHOLDER MATTERS

                        (a)   Securities Authorized For Issuance Under Equity
                              Compensation Plans: None.
                        (b)   Security Ownership Of Certain Beneficial Owners:
                              None.
                        (c)   Security Ownership Of Management: Not Applicable.
                        (d)   Changes In Control: None.

         ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

                        None.

         ITEM 14.       PRINCIPAL ACCOUNTING FEES AND SERVICES

                        Not Applicable.

                                       4
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         PART IV

         ITEM 15.          EXHIBITS, FINANCIAL STATEMENT SCHEDULES

                           (a)(1)   Financial Statements: Not Applicable

                           (a)(2)   Financial Statement Schedules: Not
                                    Applicable

                           (a)(3)   List of Exhibits

                           The following exhibits are filed as part of, and
                           incorporated by reference into this Annual Report on
                           Form 10-K:

                                    31.1     Certification of President of
                                             Registrant dated March 29, 2005,
                                             pursuant to Rules 13a-14 and 15d-14
                                             under the Securities Exchange Act
                                             of 1934, as adopted pursuant to
                                             Section 302 of the Sarbanes-Oxley
                                             Act of 2002, with respect to the
                                             Registrant's Annual Report on Form
                                             10-K for the year ended December
                                             31, 2004.

                                    99.1     Trustee's Annual Compliance
                                             Certificate dated March 24, 2005.

                                    99.2     Report of Deloitte & Touche LLP,
                                             Independent Registered Public
                                             Accounting Firm dated March 25,
                                             2005, Registrant's Assertion on
                                             Compliance with PPLUS Minimum
                                             Servicing Standards dated March 25,
                                             2005 and PPLUS Minimum Servicing
                                             Standards.

                                    99.3     Report of Ernst & Young LLP,
                                             Independent Registered Public
                                             Accounting Firm dated March 14,
                                             2005, The Bank of New York's
                                             Assertion on Compliance with PPLUS
                                             Minimum Servicing Standards dated
                                             March 14, 2005 and PPLUS Minimum
                                             Servicing Standards.

                           (b)      Exhibits

                                    The Registrant hereby files as part of this
                                    Annual Report on Form 10-K the exhibits
                                    listed in Item 15(a)(3) set forth above.

                           (c)      Financial Statement Schedules

                                    Not applicable.


                                       5

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                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, hereunto duly authorized.

                                             MERRILL LYNCH DEPOSITOR, INC.

Date:  March 29, 2005                        By:  /s/ Stephan Kuppenheimer
                                                  -----------------------------
                                                  Name:    Stephan Kuppenheimer
                                                  Title:   President