Edward G. Robinson

Character: Dr. Paul Ehrlich

Ruth Gordon

Character: Mrs. Ehrlich

Otto Kruger

Character: Dr. Emil Von Behring

Donald Crisp

Character: Minister Althoff

Maria Ouspenskaya

Character: Franziska Speyer

Montagu Love

Character: Professor Hartmann

Sig Ruman

Character: Dr. Hans Wolfert

Donald Meek

Character: Mittelmeyer

Henry O'Neill

Character: Dr. Lentz

Albert Bassermann

Character: Dr. Robert Koch

Edward Norris

Character: Dr. Morgenroth

Harry Davenport

Character: Judge

Louis Calhern

Character: Dr. Brockdorf

Louis Jean Heydt

Character: Dr. Kunze

Charles Halton

Character: Sensenbrenner

Irving Bacon

Character: Becker

Douglas Wood

Character: Speidler

Theodore von Eltz

Character: Dr. Kraus

Hermine Sterler

Character: Miss Marquardt

Louis Adlon

Character: Hospital Attendant

Herbert Anderson

Character: Medical Assistant

Louis V. Arco

Character: Dr. Bertheim

Egon Brecher

Character: Martl

Cliff Clark

Character: Haupt

Gretl Dupont

Character: Mother

Lisa Golm

Character: Nurse

John Hamilton

Character: Hirsch

Ludwig Hardt

Character: Court Clerk

Wilfred Hari

Character: Dr. Hata

Paul Harvey

Character: Defense Attorney

Ernst Hauessermann

Character: Hans Weisgart

John Henrick

Character: Dr. Bucher

Stuart Holmes

Character: Male Nurse

Frank Jaquet

Character: Banker

Frank Lackteen

Character: Arab Man

Rolf Lindau

Character: Patient

Frank Mayo

Character: Assistant in Hospital

Frederic Mellinger

Character: Court Stenographer

Greta Meyer

Character: Female Nurse

Torben Meyer

Character: Kadereit

Howard M. Mitchell

Character: Dr. Virchow

Norman Phillips Jr.

Character: Stable Boy

Paul Phillips

Character: Patient

Frank Reicher

Character: Old Man

Hedwiga Reicher

Character: Nurse

Elaine Renshaw

Character: Arab Woman

Walter O. Stahl

Character: Doctor

Robert R. Stephenson

Character: Merk - Patient

Rolla Stewart

Character: Steffi

Robert Strange

Character: Koerner

Ann E. Todd

Character: Marianne

Brandon Tynan

Character: Doctor

Wilhelm von Brincken

Character: Officer

Gisela Werbisek

Character: Mother

Wolfgang Zilzer

Character: Kellner