Cary Grant is slick showman Jerry Flynn, a Broadway producer anxious to recapture the magic and reclaim the crowds after a series of costly flops. Outside his theatre one night, Flynn meets a young boy who just might save the day. The boy shows Flynn his pride and joy inside a small box: a caterpillar named Curly that dances to "Yes Sir, That's My Baby." Word quickly spreads about the amazingly talented hoofer, and the caterpillar becomes a symbol of hope for wartime America. Soon, offers are pouring in to capitalize on this sensational insect. Will Curly go Hollywood or will Flynn's get-richer quick scheme go to the bugs?