 Sweeney Bliss (Bob Burns), champion mule raiser in Missouri, takes his prize mule Samson to London, where the British government is trying to decide whether to buy mules or tractors for its colonial troops. He is accompanied by his ritzy wife Julie (Gladys George) who has high society aspirations and hopes to have her younger sister Lola Pike (Judith Barrett) marry a British diplomat. Complicating matters is a business rival, Porgie Rowe (Gene Lockhart), who is trying to sell tractors to the government and keeps knocking Sweeney s prize Missouri mules.