While watching from her train window, Nikki Collins witnesses a murder in a nearby building. When she alerts the police, they think she has read one too many mystery novels. She then enlists a popular mystery writer to help her solve the crime on her own, but her sleuthing attracts the attentions of suitors and killers.

Deanna Durbinas Nikki Collins / Margo Martin
Ralph Bellamyas Jonathan Waring
David Bruceas Wayne Morgan
George Coulourisas Mr. Saunders, Circus Club Manager
Allen Jenkinsas Danny (Waring chauffeur)
Dan Duryeaas Arnold Waring
Edward Everett Hortonas Mr. Haskell
Patricia Morisonas Joyce Willams, Morgan's Girl
Maria Palmeras Margo Martin, Circus Club Singer
Elizabeth Pattersonas Aunt Charlotte Waring
Elwood Bredell