Exhibit 4.3


This Supplemental Indenture (this “Supplemental Indenture”), dated as of May 30, 2006, between Monitronics Canada, Inc., a Delaware corporation (the “Guaranteeing Subsidiary”), a subsidiary of Monitronics International, Inc. (or its permitted successor), a Texas corporation (the “Company”), the Company and The Bank of New York Trust Company, N.A. (or its permitted successor), as trustee under the Indenture referred to below (the “Trustee”).


WHEREAS, the Company has heretofore executed and delivered to the Trustee an indenture (the “Indenture”), dated as of August 25, 2003 providing for the issuance of 113/4% Senior Subordinated Notes due 2010 (the “Notes”);

WHEREAS, the Indenture provides that under certain circumstances the Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental indenture pursuant to which the Guaranteeing Subsidiary shall unconditionally guarantee all of the Company’s obligations under the Notes and the Indenture on the terms and conditions set forth herein (the “Note Guarantee”); and

WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture.

NOW THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

1. Capitalized Terms.  Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture.

2. Agreement to Guarantee.

(a)                                  The Guaranteeing Subsidiary, along with all other Guarantors, jointly and severally, fully and unconditionally, guarantees to each Holder of a Note authenticated and delivered by the Trustee and to the Trustee and its successors and assigns, irrespective of the validity and enforceability of the Indenture, the Notes or the obligations of the Company hereunder or thereunder, that:

(i)                                     the principal of, premium, if any, and interest and Liquidated Damages, if any, on the Notes will be promptly paid in full when due, whether at maturity, by acceleration, redemption or otherwise, and interest on the overdue principal, premium, if any, and interest and Liquidated Damages (as defined in the Indenture), if any, on the Notes, if lawful (subject in all cases to any applicable grace period provided herein), and all other obligations of the Company to the Holders or the Trustee hereunder or thereunder will be promptly paid in full or performed, all in accordance with the terms hereof and thereof.

(ii)                                  in case of any extension of time of payment or renewal of any Notes or any of such other obligations, the same will be promptly paid in full when due or performed in accordance with the terms of the extension or renewal, whether at stated maturity, by acceleration or otherwise. Failing payment when due of any amount so guaranteed or any performance so guaranteed for whatever reason, the Guaranteeing Subsidiary shall be jointly and severally obligated to pay the same immediately. The Guaranteeing Subsidiary agrees that this is a guarantee of payment and not a guarantee of collection.

(b)                                 The Guaranteeing Subsidiary hereby agrees that, to the maximum extent permitted under applicable law, its obligations hereunder shall be unconditional, irrespective of the validity, regularity or enforceability of the Notes or the Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder of the Notes with respect to any provisions hereof or thereof, the recovery of any judgment against the Company, any action to enforce the same or any other circumstance that might otherwise constitute a legal or equitable discharge or defense of a Guarantor.

(c)                                  The Guaranteeing Subsidiary, subject to Section 6.06 of the Indenture, hereby waives diligence, presentment, demand of payment, filing of claims with a court in the event of insolvency or bankruptcy of the Company, any right to require a proceeding first against the Company, protest, notice and all demands whatsoever and covenants that this Note Guarantee shall not be discharged except by complete performance of the obligations contained in the Notes and the Indenture.

(d)                                 The Guaranteeing Subsidiary agrees that if any Holder or the Trustee is required by any court or otherwise to return to the Company, the Guarantors, or any custodian, trustee, liquidator or other similar official acting in relation to any of the Company or the Guarantors, any amount paid by any of them to the Trustee or such Holder, this Note Guarantee, to the extent theretofore discharged, shall be reinstated in full force and effect.

(e)                                  The Guaranteeing Subsidiary agrees that it shall not be entitled to any right of subrogation in relation to the Holders in respect of any obligations guaranteed hereby until payment in full of all obligations guaranteed hereby.

(f)                                    The Guaranteeing Subsidiary agrees that, as between the Guarantors, on the one hand, and the Holders and the Trustee, on the other hand, (x) the maturity of the obligations guaranteed hereby may be accelerated as provided in Article Six of the Indenture for the purposes of this Note Guarantee, notwithstanding any stay, injunction or other prohibition preventing such acceleration in respect of the obligations guaranteed hereby, and (y) in the event of any declaration of acceleration of such obligations as provided in Article Six of the Indenture, such obligations (whether or not due and payable) shall forthwith become due and payable by the Guarantors for the purpose of this Note Guarantee.

(g)                                 The Guaranteeing Subsidiary shall have the right to seek contribution form any non-paying Guarantor so long as the exercise of such right does not impair the rights of Holders under the Note Guarantee.

(h)                                 The Guaranteeing Subsidiary confirms that it is the intention of such Guaranteeing Subsidiary that its Note Guarantee not constitute a fraudulent transfer or conveyance for purposes of Bankruptcy Law, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer Act or any similar federal or state law to the extent applicable to its Note Guarantee and, to effectuate the foregoing intention, agrees hereby irrevocably that the obligations of such Guaranteeing Subsidiary will be limited to the maximum amount as will, after giving effect to all other contingent and fixed liabilities of such Guaranteeing Subsidiary that are relevant under such laws, and after giving effect to any collections from, rights to receive contribution from or payments made by or on behalf of any other Guarantor in respect of the obligations of such other Guarantor under the Indenture, result in the obligations of such Guaranteeing Subsidiary under its Note Guarantee not constituting a fraudulent transfer or conveyance.

3. Agreement to Subordinate.

The Note Guarantee of each Guaranteeing Subsidiary shall be subordinated to all Senior Debt of such Guarantor, as and to the extent provided in Article Ten of the Indenture.

4. Execution and Delivery. The Guaranteeing Subsidiary agrees that the Note Guarantees shall remain in full force and effect notwithstanding any failure to endorse on each Note a notation of such Note Guarantee.

5. Guaranteeing Subsidiary May Consolidate, Etc., on Certain Terms.

(a)                                  A Guarantor may not sell or otherwise dispose of all or substantially all of its assets, or consolidate with or merge with or into (whether or not such Guarantor is the surviving Person) another Person, other than the Company or another Guarantor, unless:

(i)                                     immediately after giving effect to that transaction, no Default or Event of Default exists; and

(ii)                                  either:

(A)                              the Person acquiring the property in any such sale disposition or the Person formed by or surviving any such consolidation or merger (if other than the Guarantor) is a corporation or limited liability company organized or existing under the laws of the United States, any state thereof or the District of Columbia and assumes all the obligations of that Guarantor under the Indenture, its Note Guarantee and the Registration Rights Agreement pursuant to a supplemental indenture reasonably satisfactory to the Trustee; or

(B)                                such sale or other disposition or consolidation or merger complies with Section 4.10 of the Indenture.

(b)                                 In case of any such consolidation, merger, sale or conveyance governed by Section 4(a) hereof and upon the assumption by the successor Person, by supplemental indenture, executed and delivered to the Trustee and reasonably satisfactory in form to the

Trustee, of the Note Guarantee endorsed upon the Notes and the due and punctual performance of all of the covenants and conditions of the Indenture to be performed by a Guarantor, such successor Person shall succeed to and be substituted for a Guarantor with the same effect as if it had been named herein as a Guarantor.  Such successor Person thereupon may cause to be signed any or all of the Note Guarantees to be endorsed upon all of the Notes issuable hereunder which theretofore shall not have been signed by the Company and delivered to the Trustee.  All the Note Guarantees so issued shall in all respects have the same legal rank and benefit under the Indenture as the Note Guarantees theretofore and thereafter issued in accordance with the terms of the Indenture as though all of such Note Guarantees had been issued at the date of the execution hereof.

6. Release.

(a)                                  Any Guarantor will be released and relieved of any obligations under its Note Guarantee, (i) in connection with any sale or other disposition of all of the Capital Stock of that Guarantor to a Person that is not (either before or after giving effect to such transaction) an Affiliate of the Company, if the sale of all such Capital Stock of that Guarantor complies with Section 4.10 of the Indenture; (ii) if the Company properly designates that Guarantor as an Unrestricted Subsidiary under the Indenture or (iii) upon the release or discharge of the Guarantee which resulted in the creation of such Note Guarantee pursuant to Section 4.17(a) and (b) of the Indenture, except a discharge or release by or as a result of payment under such Guarantee.  Upon delivery by the Company to the Trustee of an Officers’ Certificate and an Opinion of Counsel to the effect that one of the foregoing requirements has been satisfied and the conditions to the release of a Guarantor under this Section 5 have been satisfied, the Trustee shall execute any documents reasonably required in order to evidence the release of such Guarantor from its obligations under its Note Guarantee.

(b)                                 Any Guarantor not released from its obligations under its Note Guarantee shall remain liable for the full amount of principal of and interest and Liquidated Damages, if any, on the Notes and for the other obligations of any Guarantor under this Supplemental Indenture.


8. Counterparts. The parties may sign any number of copies of this Supplemental Indenture.  Each signed copy shall be an original, but all of them together represent the same agreement.

9. Effect of Headings. The Section headings herein are for convenience only and shall not affect the construction hereof.

10. Trustee.  The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Guaranteeing Subsidiary and the Company.

IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed and attested, all as of the date first above written.









/s/ Michael R. Meyers





Michael R. Meyers





Vice President and
Chief Financial Officer




















/s/ Michael R. Meyers





Michael R. Meyers





Vice President and
Chief Financial Officer








The Bank of New York Trust Company, N.A.,









/s/ Tamara K. Ellis





Tamara K. Ellis





Vice President