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                                                                       Exhibit 1






                 FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

                                 BY AND BETWEEN

                                TICKETS.COM, INC.

                                       AND

                             LASERGATE SYSTEMS, INC.

                             DATED OCTOBER 20, 1999



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                 FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

        This First Amendment (this "First Amendment") to Agreement and Plan of
Merger, dated as of October 20, 1999, is by and between Tickets.com, Inc., a
Delaware corporation ("Tickets.com") and Lasergate Systems, Inc., a Florida
corporation ("LSi").

                                   BACKGROUND

        Pursuant to an Agreement and Plan of Merger, dated June 21, 1999 (the
"Agreement"), by and among Tickets.com, Advantix Acquisition Corp., a Delaware
corporation (the "Company") and LSi, the Company, upon the affirmative vote of a
majority of the shareholders of LSi, shall be merged with and into LSi and shall
become a wholly-owned subsidiary of Tickets.com. All capitalized terms used and
not otherwise defined in this First Amendment shall have the meanings ascribed
to them in the Agreement. Accordingly, in consideration of the mutual covenants
and agreements set forth below, the parties agree as follows:

                                      TERMS

1. Section 9.1 Termination. Section 9.1(b) of the Agreement is hereby amended in
its entirety to read as follows:

               (b) by Tickets.com or LSi if either (i) the Effective Time shall
        not have occurred on or before January 31, 2000; however, the right to
        terminate this Agreement under this Section 9.1(b)(i) shall not be
        available to any party whose failure to fulfill any obligation under
        this Agreement has been the cause of, or resulted in, the failure of the
        Effective Time to occur on or before such date unless such failure has
        been outside the control of such party using its reasonable efforts; or
        (ii) there shall be any statute, law, ordinance, rule, or regulation
        that makes consummation of the Merger illegal or otherwise prohibited or
        if any court of competent jurisdiction or Governmental Entity shall have
        issued an order, decree, or ruling or taken any other action
        restraining, enjoining, or otherwise prohibiting the Merger and such
        order, decree, ruling, or other action shall have become final and
        nonappealable, except such as have been sought by or on behalf of
        Tickets.com.

2. Governing Law. This First Amendment shall be governed by and construed in
accordance with the laws of Florida, without regard to any applicable conflicts
of law.

3. Agreement Remains in Effect. Except as specifically modified by this First
Amendment, the Agreement remains in full force and effect.


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4. Counterparts. This First Amendment may be executed in counterpart originals,
and by facsimile transmission, each of which counterpart original shall be
deemed one and the same instrument.

   IN WITNESS WHEREOF, the undersigned have executed this First Amendment as of
the date first written above.



                                   LASERGATE SYSTEMS, INC.



                                   By: /s/ DAVID A. RILEY
                                      ----------------------------------
                                         David A. Riley, Chief Executive
                                         Officer and President


                                   TICKETS.COM, INC.


                                   By:    /s/ Tim Kelley
                                      ----------------------------------

                                   Name:
                                        --------------------------------

                                   Title: Executive Vice President
                                         -------------------------------


