Once Upon a Time is a 1944 American comedy fantasy film involving a dancing caterpillar who lives in a small box. Cary Grant plays a conniving showman who desperately needs money to save his theater. The film was based on a 1940 radio play called "My Client Curley", adapted by Norman Corwin from a magazine story by Lucille Fletcher.

Plot

Jerry Flynn has to come up with $100,000 within a week to keep his theater. By chance, youngster Arthur "Pinky" Thompson shows him "Curly" (the original title of the film), a caterpillar that gets up on its tail and dances when Pinky plays "Yes Sir, That's My Baby" on his harmonica. Pinky refuses to let Jerry buy his friend, so they become partners. The boy is an orphan being raised by his showgirl sister Jeannie, so he soon becomes very attached to Jerry, as does his sister.