Philo Vance
Bernice
Dale Leland
Sgt. Heath
Mrs. Stamm
Markham
Rudolph Stamm
Ruby Steele
Ken Tatum
Dr. Doremus
Monty Montague
Dr. Halliday
Greeff (as William Davidson)
Trainor - Stamm's Butler
Detective Hennessey (as Charles Wilson)
Service Station Attendant (uncredited)
Police Sergeant (uncredited)
Steam Room Attendant (uncredited)
Commander (uncredited)
Detective in Diving Suit (uncredited)
Mrs. Schwartz (uncredited)
Burt - Detective (uncredited)
Detective (uncredited)
Currey - Vance's Butler (uncredited)
