Mo. Rev. Stat. § 217.460
Within one hundred eighty days after the receipt of the request and certificate, pursuant to sections 217.450 and 217.455, by the court and the prosecuting attorney or within such additional necessary or reasonable time as the court may grant, for good cause shown in open court, the offender or his counsel being present, the indictment, information or complaint shall be brought to trial. The parties may stipulate for a continuance or a continuance may be granted if notice is given to the attorney of record with an opportunity for him to be heard. If the indictment, information or complaint is not brought to trial within the period and if the court finds that the offender's constitutional right to a speedy trial has been denied, no court of this state shall have jurisdiction of such indictment, information or complaint, nor shall the untried indictment, information or complaint be of any further force or effect; and the court shall issue an order dismissing the same with prejudice.
§ 217.460, RSMo