Before Dawn

Stuart Erwin

Dwight Wilson

Dorothy Wilson

Patricia Merrick, also known as Mlle. Mystera

Warner Oland

Dr. Paul Cornelius

Dudley Digges

Horace Merrick

Gertrude Hoffmann

Mattie (as Gertrude W. Hoffman)

Oscar Apfel

Chief of Detectives John F. O'Hara

Frank Reicher

Joe Valerie

Jane Darwell

Mrs. Marble

Stanley Blystone

Police Car Driver (uncredited)

Ed Brady

Paddywagon Cop (uncredited)

Tom Brower

Detective Schultz (uncredited)

Pat O'Malley

Detective Brady (uncredited)

Ted Oliver

Police Desk Sergeant Hamilton (uncredited)

Irving Pichel

Police Radio Announcer (voice) (uncredited)