<PAGE>   1
                                                                   EXHIBIT 10.21




                              CONSENT TO ASSIGNMENT

         This CONSENT TO ASSIGNMENT (this "CONSENT") is entered into by and
among Landlord, Tenant and Assignee with reference to the following:

1.       GENERAL TERMS. All capitalized terms used in this Consent shall have
the same meanings as set forth in the Lease, unless otherwise provided below:

         a.       "EFFECTIVE DATE":    April 4, 2000

         b.       "LANDLORD":          CRESCENT REAL ESTATE FUNDING I, L.P.,
                                       a Delaware limited partnership

         c.       "TENANT":            MARCUS & PARTNERS, L.P.,
                                       a Delaware limited partnership

         d.       "ASSIGNEE":          eVENTURES GROUP, INC.,
                                       a Delaware corporation

         e.       "LEASE":             Office Lease dated May 20, 1999, as it
                                       may have been amended from time to time.

         f.       "PREMISES":          Approximately 9,377 RSF on the 8th floor
                                       of the Building.

         g.       "BUILDING":          The Crescent(R), 100, 200 and 300
                                       Crescent Court, Dallas, Texas.

         h.       "ASSIGNMENT":        Assignment of Office Lease dated
                                       effective as of April 4, 2000.

         i.       "EXCESS CONSIDERATION":   N/A.

 2.      RECITALS.

         a. Tenant is the tenant under the Lease, under which Landlord leased to
Tenant the Premises located in the Building.

         b. Tenant desires to assign all of its right, title and interest in the
Lease to Assignee.

         c. The terms of the Lease require Landlord's consent to any such
assignment.



                                                                          PAGE 1
<PAGE>   2

3. LANDLORD'S CONSENT. As of the Effective Date, Landlord consents to the
assignment of all of Tenant's right, title and interest in and under the Lease
to Assignee pursuant to the Assignment, a copy of which is attached as EXHIBIT
"A," subject to the terms and conditions of this Consent.

4. ASSUMPTION. Assignee expressly assumes and agrees to perform all of the
covenants, duties and obligations of Tenant under the Lease. Assignee
acknowledges that it has examined and is familiar with all of the terms and
provisions of the Lease.

5. PROHIBITION AGAINST FURTHER TRANSFER. Assignee shall not, without Landlord's
prior written consent in each instance in accordance with PARAGRAPH 12(c) of the
Lease, (i) convey, assign or encumber the Lease or any interest in the Lease,
directly or indirectly, voluntarily or by operation of law, including the merger
or conversion of Assignee with or into another entity, (ii) sublet all or any
portion of the Premises, or (iii) permit the use or occupancy of any part of the
Premises by anyone other than Assignee (any of the foregoing actions shall be a
"PROHIBITED TRANSFER"). If Assignee is other than an individual, any change in
Control (defined in the following sentence) of Assignee shall constitute a
Prohibited Transfer. "CONTROL" means the direct or indirect power to direct or
cause direction of the management and policies of an entity, whether through
ownership of voting securities, by contract or otherwise. Conversely, Assignee
shall not sublease space from, or assume the lease obligations of, another
tenant in the Building (or, if the Building is part of a multi-building project,
another tenant in such project) without Landlord's prior written consent.
Following any Prohibited Transfer, Assignee (and any guarantors) shall remain
fully liable under the Lease and this Consent under the terms and conditions of
the Lease as it exists on the date of the Prohibited Transfer, and Landlord may
proceed directly under the Lease or this Consent against Assignee (or any
guarantors) without first proceeding against any other party. If Landlord, or an
affiliate of Landlord, is a real estate investment trust under Section 856, et
seq. of the Internal Revenue Code of 1986, as amended ("CODE"), any Prohibited
Transfer will be void ab initio. Assignee hereby confirms that PARAGRAPH 12 of
the Lease remains valid and binding on Assignee.

6. LANDLORD'S OBLIGATIONS. Notwithstanding anything to the contrary contained in
the Assignment, subject to Landlord's release of Tenant set forth in PARAGRAPH
12, neither the Assignment nor this Consent shall (i) enlarge or increase
Landlord's obligations or liability, or (ii) reduce or decrease Landlord's
rights, under the Lease or otherwise. Landlord is not a party to the Assignment
and, therefore, is not bound by any of the terms of the Assignment.

7. EXCESS CONSIDERATION. In the event that the rental and other consideration
payable to Tenant by Assignee under the Assignment exceed the rental payable
under the Lease, then Tenant shall be bound and obligated to pay Landlord the
Excess Consideration set forth in PARAGRAPH 1.i. Tenant's failure to pay to
Landlord such amounts when due shall be an event of default under the Primary
Lease.

8. OPTIONS. Notwithstanding anything to the contrary contained in the Lease,
Landlord agrees that Assignee shall be entitled to exercise any renewal,
expansion, right of first refusal or other similar options or rights afforded to
Tenant under the Lease.



                                                                          PAGE 2
<PAGE>   3

9. BROKERAGE. Tenant and Assignee each agree to indemnify, defend and hold
Landlord and its designated property management, construction and marketing
firms harmless from and against any and all damage, loss, cost or expense,
including, without limitation, all attorneys' fees and disbursements, incurred
by reason of any claim of or liability to any broker or other person for
commissions or other compensation or charges with respect to the negotiation,
execution and delivery of the Assignment. The obligations of Tenant and Assignee
under this PARAGRAPH 9 shall survive the expiration or sooner termination of the
Lease.

10. OTHER AGREEMENTS. Other than the Lease, the Assignment and this Consent,
there are no other agreements or understandings, whether written or oral,
between Tenant and Assignee with respect to the assignment of the Lease to
Assignee or with respect to Assignee's use and occupancy of the Premises. No
compensation or consideration is payable or will become due and payable to
Tenant or any affiliate of Tenant in connection with the Assignment of Tenant's
leasehold interest other than the consideration expressly set forth in the
Assignment. This Consent shall not be amended orally, but only by an agreement
in writing signed by all parties to this Consent.

11. INDEMNITY. IN ADDITION TO ANY OTHER RIGHT OR REMEDY AVAILABLE TO LANDLORD AT
LAW, IN EQUITY, OR UNDER THE LEASE OR THIS CONSENT FOR ASSIGNEE'S VIOLATION OF
PARAGRAPH 5 OF THIS CONSENT, ASSIGNEE SHALL INDEMNIFY LANDLORD AGAINST ANY
DAMAGES, LOSSES, INJURIES, COSTS, EXPENSES OR LIABILITIES RESULTING FROM THE
FAILURE OF ANY PART OF THE GROSS INCOME FROM THE BUILDING TO QUALIFY AS "RENTS
FROM REAL PROPERTY," AS SUCH TERM IS DEFINED IN SECTION 856(D) OF THE CODE,
BECAUSE OF A PROHIBITED TRANSFER.

12. RELEASE OF TENANT. Notwithstanding anything to the contrary contained in the
Lease, effective as of April 4, 2000 (the effective date of the Assignment),
Tenant shall have no further liability or obligation to Landlord with respect to
the Lease, except for any unperformed obligations under the Lease prior to April
4,2000 and any adjustments required in connection with the payment of Excess
Operating Expenses for the 2000 calendar year (pro rated from January 1, 2000
through April 4,2000) pursuant to PARAGRAPH 7 of the Lease. Accordingly,
Landlord releases Tenant from and against any and all claims arising out of or
relating to the Lease and/or Tenant's use and occupancy of the Premises;
provided, however, all indemnities and all provisions contained in the Lease
with respect to liability insurance coverage by Tenant shall survive April
4,2000 with respect to any and all matters which shall have accrued on or before
April 4, 2000.

13. BINDING EFFECT. This Consent and its provisions shall be binding on and
inure to the benefit of the parties to this Consent and their successors and
permitted assigns.

14. RECORDING. Neither this Consent nor the Assignment may be recorded, without
Landlord's prior written consent.

15. CONFLICTS. In the event of any conflicts among the provisions of the Lease,
the Assignment and this Consent, the provisions of this Consent and the Lease
shall control; and in the event of any



                                                                          PAGE 3
<PAGE>   4

conflicts between the provisions of the Lease and this Consent, the provisions
of this Consent shall control.

          ACCORDINGLY, the parties have executed this Consent as of the
Effective Date.

LANDLORD:

CRESCENT REAL ESTATE FUNDING I, L.P.,
a Delaware limited partnership

By: CRE Management I Corp., a Delaware
    corporation, its general partner

    By: /s/ John L. Zogg, Jr.
       -------------------------------------
    Name: John L. Zogg, Jr.
         -----------------------------------
    Title: Vice President, Leasing/Marketing
          ----------------------------------


TENANT:

MARCUS & PARTNERS, L.P.,
a Delaware limited partnership

By: J & N Ventures, Inc., its general partner

    By: /s/ Jeffrey A. Marcus
       -------------------------------------
    Name: Jeffrey A. Marcus
         -----------------------------------
    Title: President, Chief Executive Officer,
           Secretary and Treasurer
          ----------------------------------


ASSIGNEE:

eVENTURES GROUP, INC.,
a Delaware corporation

    By: /s/ Jeffrey A. Marcus
       -------------------------------------
    Name: Jeffrey A. Marcus
         -----------------------------------
    Title: CEO
          ----------------------------------



                                                                          PAGE 4
<PAGE>   5

                       EXHIBIT A TO CONSENT TO ASSIGNMENT


                                  ASSIGNMENT OF
                                  OFFICE LEASE

                  THIS ASSIGNMENT OF OFFICE LEASE (this "Assignment") is made as
of this 4th day of April, 2000 (the "Effective Date"), by and between MARCUS &
PARTNERS, L.P., a Delaware limited partnership ("Assignor"), and eVENTURES
GROUP, INC. ("Assignee"). Capitalized terms not defined herein shall have the
meanings ascribed to them in the Lease (as defined below).

                                   WITNESSETH:

                  WHEREAS, Crescent Real Estate Funding I, L.P., a Delaware
limited partnership ("Landlord"), is the owner of that certain office building
located at 300 Crescent Court, Dallas, Texas 75201, which is commonly known as
the "Crescent" (the "Building");

                  WHEREAS, Landlord and Assignor are parties to that certain
Office Lease dated May 20, 1999, as amended by that certain First Amendment to
Office Lease dated March 28th, 2000 (collectively, the "Lease"), whereby
Assignor leases from Landlord approximately 9,377 rentable square feet on the
8th floor of the Building; and

                  WHEREAS, Assignor and Assignee desire to enter into this
Assignment in order to assign the Assignor's rights and interests in the Lease
to Assignee and to evidence Assignee's assumption of Assignor's obligations and
liabilities under the Lease.

                                   ASSIGNMENT:

                  NOW, THEREFORE, for valuable consideration, the receipt, and
sufficiency of which are hereby acknowledged, Assignor and Assignee agree as
follows:

1.       Assignment of Lease. Assignor hereby assigns and transfers to Assignee
         all of Assignor's right, title, claim and interest in and to the Lease.

2.       Assumption. Assignee hereby acknowledges and agrees to all of the terms
         of the Lease and accepts the foregoing assignment, and Assignee assumes
         and agrees to satisfy and perform, from and after the Effective Date,
         all the duties and obligations of the Tenant under the Lease, in
         accordance with the terms thereof.

3.       Indemnification. Assignee hereby agrees to indemnify and hold Assignor
         harmless from (i) any and all duties or obligations of the Tenant under
         the Lease arising or occurring after the Effective Date and (ii) any
         costs, damages, liabilities or expenses of any nature whatsoever which
         arise or occur subsequent to the Effective Date and result from
         Assignee's failure or inability to satisfy and/or perform the duties or
         obligations of the Tenant under the Lease from and after the Effective
         Date.



<PAGE>   6

         Assignor hereby agrees to indemnify and hold Assignee harmless from (i)
         any and all duties or obligations of the Tenant under the Lease arising
         or occurring prior to the Effective Date and (ii) any costs, damages,
         liabilities or expenses of any nature whatsoever which arise or occur
         prior to the Effective Date and result from Assignor's failure or
         inability to satisfy and/or perform the duties or obligations of the
         Tenant under the Lease prior to the Effective Date.

4.       Governing Law. This Assignment shall be governed by and construed in
         accordance with the laws of the State of Texas.

                  IN WITNESS WHEREOF, Assignor and Assignee have executed this
Assignment as of the Effective Date.


                  ASSIGNOR:            MARCUS & PARTNERS, L.P.,
                                       a Delaware limited partnership

                                       By: J&N Ventures, Inc.,
                                           its general partner


                                           By: /s/ JEFFREY A. MARCUS
                                              ----------------------------------
                                              Jeffrey A. Marcus
                                              President, Chief Executive
                                              Officer, Secretary and Treasurer


                  ASSIGNEE:            eVENTURES GROUP, INC.


                                       By: /s/ STUART CHASANOFF
                                          --------------------------------------
                                       Name: Stuart Chasanoff
                                            ------------------------------------
                                       Title: Vice President
                                             -----------------------------------



                                       2