William Powell

Philo Vance

Florence Eldridge

Sibella Greene

Ullrich Haupt

Dr. Von Blon

Jean Arthur

Ada Greene

Eugene Pallette

Sergeant Heath

E.H. Calvert

John F. X. Markham

Gertrude Norman

Mrs. Tobias Greene

Lowell Drew

Chester Greene

Morgan Farley

Rex Greene

Brandon Hurst

Sproot

Augusta Burmeister

Mrs. Mannheim

Marcia Harris

Hemming

Veda Buckland

Nurse (uncredited)

Shep Camp

Medical Examiner (uncredited)

Charles E. Evans

Lawyer Canon (uncredited)

Helena Phillips Evans

Miss O'Brien (uncredited)

Mildred Golden

Barton (uncredited)

Harry Strang

Policeman (uncredited)