In Old Chicago is a 1938 American disaster musical drama film directed by Henry King. The screenplay by Sonya Levien and Lamar Trotti was based on the Niven Busch story, "We the O'Learys". The film is a fictionalized account about the Great Chicago Fire of 1871 and stars Alice Brady as Mrs. O'Leary, the owner of the cow which started the fire, and Tyrone Power and Don Ameche as her sons. It also stars Alice Faye and Andy Devine. At the time of its release, it was one of the most expensive movies ever made.