Returning to her hometown from New York, Susan Applegate learns that she hasn't enough for the train fare and disguises herself as a twelve-year-old to travel for half the price. She hides from the conductors in the compartment of Major Philip Kirby, a military school instructor, who takes the "child" under his wing.

Ginger Rogers
as Susan Applegate

Ray Milland
as Major Kirby

Rita Johnson
as Pamela Hill

Robert Benchley
as Mr. Osborne

Diana Lynn
as Lucy Hill

Edward Fielding
as Colonel Hill

Frankie Thomas
as Cadet Osborne

Raymond Roe
as Cadet Wigton

Charles Smith
as Cadet Korner

Larry Nunn
as Cadet Babcock