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                                                                   Exhibit 10.33

                                  AMENDMENT TO

               CONSULTING, NO CONFLICT AND NONDISCLOSURE AGREEMENT


         This Amendment to Consulting, No Conflict and Nondisclosure Agreement
(this "Amendment") is entered into as of October 1, 1999 (the "Effective Date")
by and between Metrocall, Inc., a Delaware corporation (the "Company") and
Elliott H. Singer ("Singer").

                                     RECITAL
         The Company and Singer wish to amend the Consulting, No Conflict and
Nondisclosure Agreement entered into effective as of May 16, 1996 between the
Company and Singer (the "Agreement") as set forth below and in accordance with
Paragraph 17 of the Agreement.

                                   AGREEMENTS
         NOW THEREFORE, in consideration of the mutual covenants and agreements
contained herein and other good and valuable consideration, the sufficiency of
which is hereby acknowledged, the Company and Singer hereby agree as follows:

         1.       Paragraph 4 of the Agreement is hereby amended by replacing
the first sentence of Paragraph 4 with the following sentence:

         "Subject to Singer's full compliance with the terms of this Agreement
         including the conditions set forth below, the Company shall pay to
         Singer payments at a rate equal to $365,625 per year from the
         Termination Date until the fourth anniversary of the Termination Date,
         payable no less frequently than biweekly or payable in lump sum at
         Singer's option."


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         2. Paragraph 5 of the Agreement is hereby amended by replacing the
first sentence of Paragraph 5 with the following and adding the following
additional sentence:

         "Subject to Singer's full compliance with the terms of this Agreement
         including the conditions set forth below, between the Termination Date
         and the fourth anniversary of the Termination Date, Singer shall be
         entitled to participate in the life, medical, and disability benefits
         programs of the Company to the extent (i) (I) the Company can arrange
         such participation at a cost to the Company comparable to that
         applicable to covering a current employee and (II) the Company can
         obtain the agreement of its third-party insurers and stop-loss carriers
         and (ii) such participation is not prohibited by law or such as to call
         into question the otherwise applicable tax treatment for plans covering
         employees. The Company shall pay any applicable premiums."

         3. Paragraph 6 of the Agreement is hereby amended by replacing the
words "third anniversary" in the first sentence of Paragraph 6 with the words
"fourth anniversary".

         4.       This Amendment in no way shall limit or otherwise affect
Singer's options as set forth in Attachment 1 hereto.

         5. This Amendment shall become effective as of the date first above
written. Except as expressly set forth in this Amendment, this Amendment shall
not by implication or otherwise limit, impair, constitute a waiver of, or
otherwise affect the rights and remedies of either Singer or the Company under
the Agreement, and shall not amend or in any way affect the terms, conditions,
obligations, covenants or agreements contained in the Agreement, all of which
are ratified and affirmed and shall continue in full force and effect. This
Amendment shall apply and be effective only with respect to the provisions of
the Agreement specifically referred to herein. Except as specifically amended
hereby, the Agreement shall continue in full force and effect in accordance with
the provisions thereof as in existence on the date hereof. After the date
hereof, any reference to the Agreement shall mean the Agreement as amended
hereby.
         6.       This Amendment shall be construed in accordance with and
governed by the internal laws of Delaware, without giving effect to any
conflicts of law provisions.

                                       2
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         7. This Amendment may be executed in two or more counterparts, each of
which shall constitute an original but all of which when taken together shall
constitute on contract.








                                       3
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                  IN WITNESS WHEREOF, the parties hereto have duly executed this
Amendment or caused this Amendment to be duly executed by their authorized
representatives as of the day and year first above written.


                                       METROCALL, INC.


                                       By:      /s/   Vincent D. Kelly
                                       -------------------------------
                                                Vincent D. Kelly
                                                Chief Financial Officer
                                       Date:   October 1, 1999


                                       By:      /s/   Elliott Singer
                                       -----------------------------
                                                Elliott Singer
                                       Date:   October 1, 1999






                                       4
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                                                                    Attachment 1







ELLIOTT SINGER OPTIONS REPORT
AS OF OCTOBER 1, 1999

<TABLE>
<CAPTION>
    Grant Date         Grant Type          Options         Option Price      Expiration Date      Options Exercisable
                                         Outstanding

<S>                <C>                   <C>                 <C>                    <C>            <C>
    1/17/1997       Non Qualified          10,000            $ 6.00                 1/17/2007       10,000 current

     2/4/1997       Non Qualified          88,408              6.00                11/9/2004        88,408 current

     2/4/1997       Non Qualified          53,044              6.00                8/17/2005        53,044 current

     2/6/1997       Non Qualified           5,000              6.00                2/5/2007          5,000 current

    1/17/1998       Non Qualified           1,000              5.125               1/17/2008         1,000 current

     2/4/1998       Non Qualified          10,000              5.125               2/3/2008         10,000 current

    1/17/1999       Non Qualified           1,000              5.625               1/16/2009         1,000 current

     2/3/1999       Non Qualified          10,000              5.125               2/2/2009         10,000 current

                                          178,452                                                  178,452
</TABLE>