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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    FORM 10-K

                                  ANNUAL REPORT

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

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        For the fiscal year ended:                Commission file number:
             December 31, 2005                           001-16727


                          MERRILL LYNCH DEPOSITOR, INC.
                (ON BEHALF OF PREFERREDPLUS TRUST SERIES QWS-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)


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

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

PreferredPLUS Trust Certificates Series QWS-1, listed on The New York Stock
Exchange

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

Not Applicable.


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Indicate by check mark if the registrant is a well-known seasoned issuer, as
defined in Rule 405 of the Securities Act.

                           Yes [ ]             No [X]

Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Act.

                           Yes [ ]             No [X]

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 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]

Indicate by check mark whether the registrant is a shell company (as defined in
Rule 12b-2 of the Exchange Act).

                           Yes [ ]             No [X]

State the aggregate market value of the voting and non-voting common equity
held by non-affiliates computed by reference to the price at which the common
equity was last sold, or the average bid and asked price 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 classes
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
               PreferredPLUS Trust Series QWS-1, please refer to Qwest
               Communications International Inc.'s (Commission file number
               001-15577) 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 1580, 100 F Street, N.E.,
               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 100 F Street, N.E., 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 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
               their respective financial condition or creditworthiness) or of
               the underlying securities and 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 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.


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       ITEM 1A.  RISK FACTORS

                 Your investment in the trust certificates will involve certain
                 risks. You should carefully consider the following discussion
                 of risks, and the other information included or incorporated by
                 reference in the applicable prospectus supplement and the
                 accompanying prospectus. You should also carefully consider any
                 risk factors and other information that the underlying
                 securities guarantor may file in its Exchange Act reports as
                 referenced in Item 1 above.

                 IF THE UNDERLYING SECURITIES ARE REDEEMED PRIOR TO THEIR
                 MATURITY DATE OR IF ANY CALL WARRANTS ARE EXERCISED, YOU MAY
                 NOT BE ABLE TO REINVEST YOUR REDEMPTION OR CALL PROCEEDS AT A
                 YIELD COMPARABLE TO THE YIELD YOU WOULD HAVE RECEIVED ON YOUR
                 TRUST CERTIFICATES

                 The yield you will realize on your trust certificates depends
                 upon several factors, including:

                 o   the purchase price of the trust certificates,

                 o   when you acquire your trust certificates,

                 o   whether the underlying securities issuer exercises its
                     option to redeem the underlying securities, and

                 o   whether the call warrant holders exercise their optional
                     rights to purchase outstanding trust certificates.

                 The underlying securities issuer has the right to redeem the
                 underlying securities at its option. Because the underlying
                 securities issuer has the right to redeem the underlying
                 securities early, we cannot assure you that the trust will be
                 able to hold the underlying securities until their maturity
                 date.

                 Although the call warrant holders are not obligated to exercise
                 the call warrants, the yield you will realize on your trust
                 certificates depends on whether the call warrant holders
                 exercise their call warrants to purchase the trust
                 certificates. Prevailing interest rates at the time of an early
                 redemption or a call exercise may be lower than the yield on
                 your trust certificates. Therefore, you may be unable to
                 realize a comparable yield upon reinvesting the funds you
                 receive from an early redemption or exercise of any call
                 warrants. In addition, if the prevailing market value of the
                 trust certificates exceeds the redemption price call exercise
                 price paid to you upon a redemption of the underlying
                 securities or the exercise of a call, you will not be able to
                 realize such excess.


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                 YOU MAY NOT BE PAID IF THE ASSETS OF THE TRUST ARE INSUFFICIENT

                 Currently, the trust has no significant assets other than the
                 underlying securities. If the underlying securities are
                 insufficient to make payments or distributions on the trust
                 certificates, no other assets will be available for payment of
                 the deficiency.

                 THE TRUSTEE WILL NOT MANAGE THE UNDERLYING SECURITIES

                 Except as described below, the trust will not dispose of any
                 underlying securities, even if an event occurs that adversely
                 affects the value of the underlying securities or that
                 adversely affects the underlying securities issuer. As provided
                 in the applicable trust agreement, the trust will dispose of
                 the underlying securities only if:

                 o   there is a payment default on any underlying securities,

                 o   there is another type of default that accelerates the
                     maturity of the underlying securities, or

                 o   the underlying securities guarantor ceases to file Exchange
                     Act reports.

                 Under the first circumstance listed above, the trustee must
                 sell the underlying securities on behalf of the trust, even if
                 adverse market conditions exist. The trustee has no discretion
                 to do otherwise. If adverse market conditions do exist at the
                 time of the trustee's sale of the underlying securities, you
                 may incur greater losses than if the trust continued to hold
                 the underlying securities.

                 THE TRUST CERTIFICATES ARE SUBJECT TO THE CREDITWORTHINESS OF
                 THE UNDERLYING SECURITIES ISSUER AND THE UNDERLYING SECURITIES
                 GUARANTOR

                 The trust certificates represent interests in obligations of
                 the underlying securities issuer and the underlying securities
                 guarantor. In particular, the trust certificates will be
                 subject to all the risks associated with directly investing in
                 both the underlying securities issuer's and the underlying
                 securities guarantor's unsecured subordinated debt obligations.
                 Neither the underlying indenture nor the underlying securities
                 place a limitation on the amount of indebtedness that may be
                 incurred by the underlying securities issuer or the underlying
                 securities guarantor.

                 THE PAYMENTS OWED TO THE TRUST CERTIFICATEHOLDERS ARE UNSECURED
                 OBLIGATIONS

                 In a liquidation, holders of the underlying securities,
                 including the trust, will be paid only after holders of secured
                 obligations of the underlying securities issuer. According to
                 the underlying securities prospectus, the underlying securities
                 are general unsecured obligations of the underlying securities
                 issuer, which rank equally with all other unsecured and
                 unsubordinated indebtedness of the underlying securities
                 issuer. However, if the underlying securities issuer subjects
                 any of its property to a lien then the underlying securities,
                 and any other obligations which are then outstanding and
                 subject to a similar covenant, will be secured ratably with the
                 indebtedness or obligation secured by that lien and for the
                 same length of time, subject to certain exceptions.

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                 THE RIGHTS OF THE TRUST CERTIFICATEHOLDERS THROUGH THE
                 GUARANTEE TO PARTICIPATE IN ANY DISTRIBUTION OF ASSETS OF A
                 SUBSIDIARY OF THE UNDERLYING SECURITIES GUARANTOR COULD BE
                 FOUND TO BE SUBORDINATE TO THE PRIOR CLAIMS OF THE CREDITORS OF
                 SUCH SUBSIDIARY

                 The underlying guarantee is an unsecured obligation of the
                 underlying securities guarantor and ranks equally with all
                 other unsecured and unsubordinated indebtedness of the
                 underlying securities guarantor. However, because the
                 underlying securities guarantor is a holding company that
                 conducts substantially all of its operations through
                 subsidiaries, the right of the underlying securities guarantor,
                 and hence the right of creditors of the underlying securities
                 guarantor (including holders of the underlying securities
                 through the guarantee), to participate in any distribution of
                 assets of any subsidiary upon its liquidation or reorganization
                 or otherwise is necessarily subject to the prior claims of
                 creditors of such subsidiary, except to the extent that claims
                 of the underlying securities guarantor itself as a creditor of
                 the subsidiary may be recognized.

                 THE RATINGS OF THE TRUST CERTIFICATES MAY CHANGE

                 At the time of issuance, Moody's and/or S&P assigned ratings to
                 the trust certificates equivalent to the ratings of the
                 underlying securities as of the date of the applicable
                 prospectus supplement.

                 Any rating issued with respect to the trust certificates is not
                 a recommendation to purchase, sell or hold a security. Ratings
                 do not comment on the market price of the trust certificates or
                 their suitability for a particular investor. We cannot assure
                 you that initial ratings will remain for any given period of
                 time or that a ratings agency would not revise or withdraw
                 entirely the ratings if, in its judgment, circumstances
                 (including, without limitation, the rating of the underlying
                 securities) merit. A revision or withdrawal of a rating may
                 adversely affect the market price of the trust certificates.

ITEM 1B.         UNRESOLVED STAFF COMMENTS

                 Not Applicable.

ITEM 2.          PROPERTIES

                 None.

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ITEM 3.          LEGAL PROCEEDINGS

                 None.

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

                 None.

PART II

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

                 The Trust Certificates issued by PreferredPLUS Trust Series
                 QWS-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.

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ITEM 9B.         OTHER INFORMATION

                 None.

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.

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


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                 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 27, 2006, 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, 2005.

                     99.1.   Trustee's Annual Compliance Certificate dated
                             February 21, 2006.

                     99.2.   Report of Deloitte & Touche LLP, Independent
                             Registered Public Accounting Firm, dated March 24,
                             2006, Registrant's Assertion on Compliance with
                             PPLUS Minimum Servicing Standards dated March 24,
                             2006 and PPLUS Minimum Servicing Standards.

                     99.3.   Report of Ernst & Young LLP, Independent Registered
                             Public Accounting Firm, dated February 21, 2006,

                             The Bank of New York's Assertion on Compliance with
                             PPLUS Minimum Servicing Standards dated February
                             21, 2006 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.

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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.

March 27, 2006                            By: /s/ Stephan Kuppenheimer
                                             ------------------------------
                                              Name:  Stephan Kuppenheimer
                                              Title: President