SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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


                                   FORM 10-K/A

                                 AMENDMENT NO.1

                                  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, 2003                                     001-32019

                          MERRILL LYNCH DEPOSITOR, INC.
                (ON BEHALF OF PREFERREDPLUS TRUST SERIES MSD-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:

PreferredPLUS Trust Certificates Series MSD-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


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for such shorter period that the Registrant was required 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.



                       DOCUMENTS INCORPORATED BY REFERENCE

None.


                                EXPLANATORY NOTE

Merrill Lynch Depositor, Inc. (on behalf of PreferredPLUS Trust Series MSD-1)
hereby amends its Annual Report for the fiscal year ended December 31, 2003 in
its entirety as set forth below.

     PART I

     Item 1.   Business


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               For information with respect to the underlying securities held by
               PreferredPLUS Trust Series MSD-1, please refer to Morgan
               Stanley's (Commission file number 001-11758) periodic reports,
               including annual reports on Form 10-K, quarterly reports on Form
               10-Q and current reports on Form 8-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 issuer has filed
               electronically with the SEC.

               Although we have no reason to believe the information concerning
               the underlying securities or the underlying securities issuer
               contained in the underlying securities issuer'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 issuer (including, without limitation, no
               investigation as to its financial condition or creditworthiness)
               or of the underlying securities has been made. You should obtain
               and evaluate the same information concerning the underlying
               securities issuer 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. There can
               be no assurance that events affecting the underlying securities
               or the underlying securities issuer have not occurred or have not
               yet been publicly disclosed which would affect the accuracy or
               completeness of the publicly available documents described above.

     Item 2.   Properties

               None.

     Item 3.   Legal Proceedings

               None.

     Item 4.   Submission of Matters to a Vote of Security Holders

               None.

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     PART II

     Item 5.   Market for Registrant's Common Equity and Related Stockholder
               Matters

               The Trust Certificates issued by PreferredPLUS Trust Series
               MSD-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's annual report on Form 10-K filed with the
               Securities and Exchange Commission on January 26, 2004 for the
               fiscal year ended December 31, 2003, and as amended hereby, did
               not include as an exhibit (i) a trustee report on compliance with
               the Standard Terms for Trust Agreements dated February 20, 1998,
               as amended, between the Registrant and the Trustee, (ii) an
               independent accountants' report attesting to management's
               assertion that the Registrant complied with its PPLUS Minimum
               Servicing Standards and (iii) a certification by the chief
               executive officer of the Registrant certifying to such compliance
               with servicing standards. The Registrant has revised its
               procedures so as to provide reasonable assurance that its future
               Exchange Act filings will be filed within the applicable time
               periods.


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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 Party Transactions

               None.

     Item 14.  Principal Accounting Fees and Services

               Not Applicable.

     PART IV

     Item 15.  Exhibits, Financial Statement Schedules and Reports on Form 8-K

               (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 Amendment No. 1 on Form 10-K/A to the
               Registrant's Annual Report on Form 10-K:


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                     31.1  Certification of President of Registrant dated March
                           30, 2004, 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, 2003.

                    99.1.  Trustee's Annual Compliance Certificate dated March
                           30, 2004.

                    99.2.  Independent Accountants' Report dated March 30, 2004,
                           Management's Assertion on Compliance with PPLUS
                           Minimum Servicing Standards dated March 30, 2004 and
                           PPLUS Minimum Servicing Standards.

               (b)   Reports on Form 8-K

                     Trustee's report in respect of the April 1, 2003
                     distribution to holders of the PreferredPLUS Trust
                     Certificates Series MSD-1 incorporated herein by reference
                     as Exhibit 99.1 to Registrant's Current Report on Form 8-K
                     filed with the Securities and Exchange Commission on April
                     17, 2003.

                     Trustees report in respect of the October 1, 2003
                     distribution to holders of the PreferredPLUS Trust
                     Certificates Series MSD-1 incorporated herein by reference
                     as Exhibit 99.1 to Registrant's Current Report on Form 8-K
                     filed with the Securities and Exchange Commission on
                     October 3, 2003.

               (c)   Exhibits

                     The Registrant hereby files as part of this Amendment No. 1
                     on Form 10-K/A to its Annual Report on Form 10-K the
                     exhibits listed in Item 15(a)(3) set forth above.


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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 30, 2004                       By: /s/ Michael Frank Connor
                                               -----------------------------
                                               Name:    Michael Frank Connor
                                               Title:   President