Mo. Rev. Stat. § 428.120
Any person who has real or personal property or an interest therein, which is subject to a recorded nonconsensual common law lien, who believes such lien is invalid, may petition the circuit court of the county in which the lien has been recorded or filed for an order, which may be granted ex parte, directing the lien claimant to appear before the court within ten business days following the date of service of the petition and order on the lien claimant, and show cause, if any, why the claim of lien should not be declared void and other relief provided for by section 428.125 should not be granted. The petition shall state the grounds upon which relief is requested, and shall be supported by the affidavit of the petitioner or the petitioner's attorney setting forth a concise statement of the facts upon which the claim for relief is based.
§ 428.120, RSMo