Ronald Colman (40)

Dr. Martin Arrowsmith

Helen Hayes (31)

Leora Tozer Arrowsmith

Richard Bennett (61)

Gustav Sondelius

A.E. Anson (52)

Professor Max Gottlieb

Clarence Brooks (34)

Dr. Oliver Marchand

Alec B. Francis (64)

Twyford

Claude King (56)

Dr. Tubbs

Bert Roach (40)

Bert Tozer

Myrna Loy (26)

Joyce Lanyon

Russell Hopton (31)

Terry Wickett

David Landau (52)

State Veterinarian

Lumsden Hare (56)

Sir Robert Fairland

Erville Alderson (49)

Pioneer (uncredited)

Ward Bond (28)

Cop (uncredited)

Beulah Bondi (43)

Mrs. Tozer (uncredited)

Florence Britton (21)

Miss Twyford (uncredited)

Nora Cecil (53)

Nurse (uncredited)

Sidney De Gray (65)

Dr. Hesselink (uncredited)

Cyril Delevanti (42)

Committee Member (uncredited)

Walter Downing

City Clerk (uncredited)

Gibson Gowland (54)

Committee Member (uncredited)

Sherry Hall (39)

Reporter (uncredited)

Theresa Harris (24)

Native Mother (uncredited)

Raymond Hatton (44)

Drunk (uncredited)

Charlotte Henry (17)

Pioneer Girl (uncredited)

George Humbert (51)

Italian Uncle (uncredited)

DeWitt Jennings (60)

B.W. Tozer (uncredited)

Mike Lally (31)

Reporter (uncredited)

Lillian Lawrence

West Indies Townswoman at Meeting (uncredited)

Carl M. Leviness (46)

Ship's Passenger (uncredited)