Dr. Constance Petersen
John Ballantine
Dr. Murchison
Dr. Alexander Brulov
Dr. Fleurot
Dr. Graff
Dr. Hanish
Dr. Galt (uncredited)
Mr. Garmes
Harry
Mary Carmichael
House detective
Det. Lt. Cooley
Det. Sgt. Gillespie
Hotel masher
Matron (uncredited)
Railway Gateman (uncredited)
Ticket Taker (uncredited)
Gateman (uncredited)
John Ballantine as a Boy (uncredited)
Nurse (uncredited)
Dr. Anthony Edwardes (uncredited)
Man Leaving Elevator (uncredited)
John Ballantine's Brother (uncredited)
