While the Patient Slept

Aline MacMahon

Nurse Sarah Keate

Guy Kibbee

Detective Lt. Lance O'Leary

Patricia Ellis

March Federie, Richard's Granddaughter

Hobart Cavanaugh

Eustace Federie

Dorothy Tree

Mittie Federie

Robert Barrat

Adolphe Federie

Helen Flint

Isobel Federie - Adolphe's Wife

Lyle Talbot

Ross Lonergan

Henry O'Neill

Elihu Dimuck

Walter Walker

Richard Federie

Allen Jenkins

Police Sgt. Jim Jackson

Sin foto

Eddie Shubert

Detective Muldoon

Russell Hicks

Dr. Jay

Brandon Hurst

Grondal - the Butler

Joseph E. Bernard

'Murph' Murphy - the Ballistics Expert (uncredited)

George Chandler

Evening Bulletin Reporter (uncredited)

Sin foto

Nick Copeland

Detective Davis aka Johnson (uncredited)

Joseph Crehan

Evening Bulletin Editor (uncredited)

Bill Elliott

Bank Teller (uncredited)

Virginia Howell

Kema - the Cook (uncredited)

Milton Kibbee

Evening Bulletin Archivist (uncredited)

Sin foto

Henry Otho

Frank - Detective (uncredited)

John J. Richardson

Reporter (uncredited)

Ferdinand Schumann-Heink

Reporter (uncredited)

Sin foto

Harry Seymour

Photographer (uncredited)

Sin foto

Huey White

Sarah's Taxi Driver (uncredited)

Sin foto

Jack Wise

Reporter (uncredited)