UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 10-K

[X]      Annual  report  pursuant  to  Section  13 or  15(d)  of the Securities
         Exchange   Act  of  1934  for the  fiscal year ended December 31, 2005

[ ]      Transition report pursuant to Section 13 or 15(d) of the
         Securities Exchange Act of 1934 for the transition period from   to


                                          Commission File Number 333-127233-20

                     MERRILL LYNCH MORTGAGE INVESTORS, INC.
             (Exact name of registrant as specified in its charter)

         Delaware                                            13-3416059
State or other jurisdiction of                           (I.R.S. Employer
incorporation or organization                            Identification No.)

250 Vesey Street
4 World Financial Center 28th Floor
New York, New York                                              10080
(Address of Principal Executive Offices)                      (Zip Code)

       Registrant's telephone number, including area code : (212) 449-0357

              Specialty Underwriting and Residential Finance Trust
            Mortgage Loan Asset-Backed Certificates, Series 2005-BC4
            (Title of each class of securities covered by this Form)

Securities registered pursuant to Section 12(b) of the Act: None
Securities registered pursuant to Section 12(g) of the Act: None

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 (229.405 of this chapter) 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. [X]

Indicate by check mark whether the registrant is a large  accelerated  filer, an
accelerated  filer, or a  non-accelerated  filer. See definition of "accelerated
filer and large accelerated filer" in Rule 12b-2 of the Exchange Act.

Large accelerated filer [ ]   Accelerated filer [ ]   Non-accelerated filer [X]

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Exchange Act Rule 12b-2). Yes  No [X]

Indicate by check mark whether the registrant is a shell company (as
defined in Exchange Act Rule 12b-2). 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 of each of the registrant's
classes of common stock, as of the latest practicable date.  Not Applicable.

Documents incorporated by reference:  None


<PAGE>


PART I

Item 1.  Business.

         Not Applicable.

Item 1A. Risk Factors.

         Not Applicable.

Item 1B. Unresolved Staff Comments.

         None.

Item 2.  Properties.

         Not Applicable.

Item 3.  Legal Proceedings.

     The Registrant knows of no material pending legal proceedings involving the
trust  created  under the Pooling and  Servicing  Agreement,  the  Trustee,  any
Servicer  or the  Registrant  with  respect  to the  trust  other  than  routine
litigation incidental to the duties of the respective parties.

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.

     Currently,  there is no established  secondary  market for the Certificates
known to the Registrant.  As of December 31, 2005, the number of holders of each
class of offered certificates was 44 based on records provided by DTC.

Item 6.  Selected Financial Data.

         Not Applicable.

Item 7.  Management's Discussion and Analysis of Financial Condition and
         Results of Operation.

         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.

         Not Applicable.

Item 9B. Other Information.

         Not Applicable.

                                      -2-

<PAGE>

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.

         Not Applicable.

Item 13. Certain Relationships and Related Transactions.

         No reportable transactions have occurred.

Item 14. Principal Accounting Fees and Services.

         Not Applicable.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

(a) The following documents are filed as part of this report:

    (1)  Financial Statements:

         Not Applicable.

    (2)  Financial Statement Schedules:

         Not Applicable.

    (3)  Exhibits:

         Rule 13a-14(a)/15d-14(a) Certification, filed as 31.1 hereto.

         Annual Independent Accountants' Servicing Report
         with Management Assertion, filed as Exhibit 99.1 hereto.

         Servicer's Annual Statement as to Compliance,
         filed as Exhibit 99.2 hereto.

(b) Exhibits to this report are listed in Item (15)(a)(3)above.

(c) Not Applicable.


                                      -3-
<PAGE>

SIGNATURE

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 thereunto duly authorized.


                        MERRILL LYNCH MORTGAGE INVESTORS TRUST
                        Mortgage Loan Asset-Backed Certificates,
                        Series 2005-BC4
                        (Registrant)

                Signed: Wilshire Credit Corp as Servicer

                    By: /s/ Jay H. Memmott, Chairman, President and CEO
                        -----------------------------------------------
                    By: Jay H. Memmott, Chairman, President and CEO
                  Date: March 29, 2006





                                      -4-
<PAGE>

SUPPLEMENTAL  INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO SECTION
15(D) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED SECURITIES PURSUANT TO
SECTION 12 OF THE ACT.

The  registrant  has not sent an annual report or proxy material to its security
holders.  The registrant  will not be sending an annual report or proxy material
to its security holders subsequent to the filing of this form.

                                      -5-
<PAGE>




                                 EXHIBIT INDEX

Exhibit     Description

 31.1       Rule 13a-14(a)/15d-14(a) Certification

 99.1       Annual Independent Accountants' Servicing Report
            with Management Assertion

            Wilshire Credit Corporation, as Servicer

 99.2       Annual Servicer's Statement as to Compliance

            Wilshire Credit Corporation, as Servicer

                                      -6-

<PAGE>
                                  EXHIBIT 31.1
                  Annual Rule 13a-14(a)/15d-14(a) Certification


     I, Jay H. Memmott, certify that:

1.   I have reviewed  this annual  report on Form 10-K,  and all reports on Form
     8-K  containing  distribution  or  servicing  reports  filed in  respect of
     periods  included in the year covered by this annual  report,  of Specialty
     Underwriting  and  Residential  Finance Trust  Mortgage  Loan  Asset-Backed
     Certificates, Series 2005-BC4;

2.   Based on my knowledge,  the information in these reports, taken as a whole,
     does not contain any untrue statement of a material fact or omit to state a
     material  fact  necessary  to make  the  statements  made,  in light of the
     circumstances  under which such  statements were made, not misleading as of
     the last day of the period covered by this annual report;

3.   Based on my knowledge,  the distribution or servicing  information required
     to be  provided  to the  trustee  by the  servicer  under the  pooling  and
     servicing,  or  similar,  agreement,  for  inclusion  in these  reports  is
     included in these reports;

4.   I am responsible  for reviewing the  activities  performed by the servicer
     under the pooling and  servicing,  or similar,  agreement and based upon my
     knowledge and the annual  compliance  review required under that agreement,
     and except as  disclosed in the reports,  the  servicer has  fulfilled  its
     obligations under that agreement; and

5.   The  reports  disclose  all  significant   deficiencies   relating  to  the
     servicer's  compliance with the minimum servicing  standards based upon the
     report provided by an independent  public  accountant,  after  conducting a
     review in  compliance  with the  Uniform  Single  Attestation  Program  for
     Mortgage  Bankers or similar  procedure,  as set forth in the  pooling  and
     servicing, or similar, agreement, that is included in these reports.

     In giving the certifications above, I have reasonably relied on information
provided to me by JPMorgan Chase Bank, N.A.,as Trustee.

                        MERRILL LYNCH MORTGAGE INVESTORS TRUST
                        Mortgage Loan Asset-Backed Certificates,
                        Series 2005-BC4
                        (Registrant)

                Signed: Wilshire Credit Corp as Servicer

                    By: /s/ Jay H. Memmott, Chairman, President and CEO
                        -----------------------------------------------
                    By: Jay H. Memmott, Chairman, President and CEO
                  Date: March 29, 2006

                                       -7-
<PAGE>


                                  EXHIBIT 99.1
               Annual Independent Accountants' Servicing Report
                            with Management Assertion
                               ------------------

                                                Deloitte & Touche LLP
                                                Suite 3900
                                                111 SW Fifth Avenue
                                                Portland, OR  97204-3642
                                                USA
                                                Tel: +1 503 222 1341
                                                Fax: +1 503 224 2172
                                                www.deloitte.com



REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Directors
Wilshire Credit Corporation:

We have examined  management's  assertion that Wilshire  Credit  Corporation,  a
wholly owned  subsidiary of Merrill Lynch  Mortgage  Capital Inc., a division of
Merrill  Lynch & Co., New York, NY (the  "Company"),  has complied as of and for
the year  ended  December  31,  2005,  with its  established  minimum  servicing
standards  described  in the  accompanying  Management's  Assertion  on  Minimum
Servicing  Standards dated February 27, 2006.  Management is responsible for the
Company's compliance with those minimum servicing standards.  Our responsibility
is  to  express  an  opinion  on  management's  assertion  about  the  Company's
compliance based on our examination.

Our  examination  was  conducted  in  accordance  with   attestation   standards
established  by the  American  Institute  of Certified  Public  Accountants,  as
adopted  by the  Public  Company  Accounting  Oversight  Board and  accordingly,
included  examining,  on a test basis,  evidence about the Company's  compliance
with its minimum servicing  standards and performing such other procedures as we
considered  necessary  in the  circumstances.  We believe  that our  examination
provides a reasonable basis for our opinion.  Our examination does not provide a
legal  determination  on the  Company's  compliance  with its minimum  servicing
standards.

In our  opinion,  management's  assertion  that the  Company  complied  with the
aforementioned minimum servicing standards as of and for the year ended December
31, 2005, is fairly stated, in all material respects,  based on the criteria set
forth in Appendix I.


By:  /s/ Deloitte & Touche LLP
     -------------------------
     February 27, 2006


                                      -8-
<page>
                                                                       Wilshire

                            MANAGEMENT'S ASSERTION ON
                           MINIMUM SERVICING STANDARDS


As of and for the year ended December 31, 2005, Wilshire Credit Corporation (the
"Company")  has  complied,   in  all  material  respects,   with  the  Company's
established  minimum servicing  standards for residential  mortgage loans as set
forth in Appendix I (the  "Standards").  The Standards are based on the Mortgage
Bankers  Association  of  America's  Uniform  Single  Attestation  Program  for
Mortgage Bankers.

As of and for this same period, the Company had in effect a fidelity bond in the
amount  of  $265,000,000  and an errors  and  omission  policy in the  amount of
$25,000,000.


By:  /s/ Jay Memmott
    -------------------------------------------------
    Jay Memmott, President and Chief Executive Officer
    Wilshire Credit Corporation
    Feb 27, 2006

By:  /s/ Russell Campbell
    -------------------------------------------------
    Russell Campbell, Chief Investment Officer
    Wilshire Credit Corporation
    Feb 27, 2006

By:  /s/ Ken Frye
    -------------------------------------------------
    Ken Frye, Senior Vice President
    Wilshire Credit Corporation
    Feb 27, 2006

                                       -9-
<page>

                                                                     APPENDIX I

MINIMUM SERVICING STANDARDS AS SET FORTH IN THE MORTGAGE BANKERS
ASSOCIATION OF AMERICA'S UNIFORM SINGLE ATTESTATION PROGRAM FOR
MORTGAGE BANKERS

I.   CUSTODIAL BANK ACCOUNTS

1.   Reconciliations shall be prepared on a monthly basis for all custodial bank
     accounts and related bank clearing accounts. These reconciliations shall:

      .  Be mathematically accurate

      .  Be prepared within forty-five (45) calendar days after the cutoff date

      .  Be reviewed and approved by someone other than the person who prepared
         the reconciliation

      .  Document explanations for reconciling items.  These reconciling items
         shall be resolved within ninety (90) calendar days of their original
         identification.

2.   Funds of the servicing  entity shall be advanced in cases where there is an
     overdraft in an investor's or a mortgagor's account.

3.   Each  custodial   account  shall  be  maintained  at  a  federally  insured
     depository institution in trust for the applicable investor.

4.   Escrow  funds  held in  trust  for a  mortgagor  shall be  returned  to the
     mortgagor within thirty (30) calendar days of payoff of the mortgage loan.

II.  MORTGAGE PAYMENTS

1.   Mortgage  payments  shall be deposited into the custodial bank accounts and
     related bank clearing accounts within two business days of receipt.

2.   Mortgage  payments made in accordance with the  mortgagor's  loan documents
     shall be posted to the  applicable  mortgagor  records  within two business
     days of receipt.

3.   Mortgage  payments  shall be allocated to principal,  interest,  insurance,
     taxes or  other  escrow  items in  accordance  with  the  mortgagor's  loan
     documents.

4.   Mortgage  payments  identified  as  loan  payoffs  shall  be  allocated  in
     accordance with the mortgagor's loan documents.

III. DISBURSEMENTS

1.   Disbursements  made via wire  transfer on behalf of a mortgagor or investor
     shall be made only by authorized personnel.

2.   Disbursements  made on behalf of a mortgagor  or  investor  shall be posted
     within  two  business  days  to  the  mortgagor's  or  investor's   records
     maintained by the servicing entity.

3.   Tax and  insurance  payments  shall be made on or  before  the  penalty  or
     insurance policy  expiration dates, as indicated on tax bills and insurance
     premium notices, respectively, provided that such support has been received
     by the  servicing  entity at least thirty (30) calendar days prior to these
     dates.

4.   Any late payment  penalties paid in conjunction with the payment of any tax
     bill or insurance premium notice shall be paid from the servicing  entity's
     funds and not charged to the mortgagor,  unless the late payment was due to
     the mortgagor's error or omission.

5.   Amounts  remitted to investors per the  servicer's  investor  reports shall
     agree with cancelled  checks,  or other form of payment,  or custodial bank
     statements.

6.   Unused checks shall be safeguarded so as to prevent unauthorized access.

IV.  INVESTOR ACCOUNTING AND REPORTING

     The servicing  entity's investor reports shall agree with, or reconcile to,
     investors'  records  on a monthly  basis as to the total  unpaid  principal
     balance and number of loans serviced by the servicing entity.

V.   MORTGAGOR LOAN ACCOUNTING

1.   The servicing entity's mortgage loan records shall agree with, or reconcile
     to, the records of mortgagors with respect to the unpaid principal  balance
     on a monthly basis.

2.   Adjustments  on ARM loans shall be computed  based on the related  mortgage
     note and any ARM rider.

3.   Escrow accounts shall be analyzed,  in accordance with the mortgagor's loan
     documents, on at least an annual basis.

4.   Interest on escrow  accounts  shall be paid, or credited,  to mortgagors in
     accordance with the applicable state laws.

VI.  DELINQUENCIES

1.   Records  documenting  collection  efforts  shall be  maintained  during the
     period a loan is in default  and shall be updated  at least  monthly.  Such
     records shall  describe the entity's  activities  in monitoring  delinquent
     loans  including,  for example,  phone calls,  letters and mortgage payment
     rescheduling  plans in cases  where the  delinquency  is  deemed  temporary
     (e.g., illness or unemployment).

VII. INSURANCE POLICIES

1.   A fidelity bond and errors and  omissions  policy shall be in effect on the
     servicing entity  throughout the reporting period in the amount of coverage
     represented to investors in management's assertion.

                                      -10-
<page>


                                  EXHIBIT 99.2
                   Annual Servicer's Statement as to Compliance
                               ------------------

                                      WILSHIRE CREDIT CORPORATION

                                      Payments
                                      P.O. Box 30040, Los Angeles, CA 90030-0040
                                      or P.O. Box 650314, Dallas, TX 75265-0314
                                      Correspondence
                                      P.O. Box 8517, Portland, OR 97207-8517
                                      Phone
                                      (503) 952-7947
                                      (888) 502-0100
                                      Fax
                                      (503) 952-7476
                                      Web Site
                                      www.wfsg.com

March 10, 2006

JPMorgan Chase Bank, N.A.
600 Travis Street, 9th Floor
Houston, TX  77002-3009
Attn: Josie Jimenez

Merrill Lynch Mortgage Investors, Inc.
250 Vesey Street
4 World Financial Center
10th Floor
New York, NY  10080
Attn: Asset-Backed Finance

Re:  Pooling and Servicing Agreements as Described on Exhibit A.

                    Annual Servicing Officer's Certification

I, Jay H.  Memmott,  certify  to the  Trustee  and to the  Depositor  and  their
officers,  directors and affiliates, and with the knowledge and intent that they
will rely upon this certification, that:

I.   A review of the  activities of the Servicer  during the preceding  calendar
     year and of its performance  under the referenced  Servicing  Agreement has
     been made under my Supervision; and

II.  To the  best  of my  knowledge,  based  on the  review,  the  Servicer  has
     materially  fulfilled all of its obligations under the Servicing Agreements
     throughout  the year except as disclosed in writing on or prior to the date
     of this certification  either in the accountants' report required under the
     related Agreements or in disclosure a copy of which is attached hereto.

Wilshire Credit Corporation, as Servicer

Certified by:

By: /s/ Jay H. Memmott
--------------------------------------
Name:  Jay H. Memmott
Title: Chairman, President, & CEO


                                      -11-

<page>

                           JPMORGAN CHASE BANK - SURF
                                   EXHIBIT A

Pool   Description         Verbiage

1400   MLMI SURF 2005-AB1  Pooling and Servicing  Agreement  dated as of
                           May 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-AB1

1401   MLMI SURF 2005-BC2  Pooling and Servicing  Agreement  dated as of
                           May 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-BC2

1402   MLMI SURF 2005-BC3  Pooling and Servicing  Agreement  dated as of
                           September 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-BC3

1403   MLMI SURF 2005-AB2  Pooling and Servicing  Agreement  dated as of
                           September 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-AB2

1404   MLMI SURF 2005-BC4  Pooling and Servicing  Agreement  dated as of
                           December 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-BC4

1405   MLMI SURF 2005-AB3  Pooling and Servicing  Agreement  dated as of
                           December 1, 2005,  between Merrill Lynch Mortgage
                           Investors, Inc., Depositor, Wilshire Credit
                           Corporation, Servicer, and JPMorgan Chase Bank,
                           National Association, Trustee for the Specialty
                           Underwriting and Residential Finance Trust Series
                           2005-AB3

                                      -12-