Derek Farr

Character: Ivan Mason / Dr. James Paxton

Ella Raines

Character: Rhona Ellison

Donald Wolfit

Character: Prof. Cattrell

Lisa Daniely

Character: Nurse Mitzi

Bruce Beeby

Character: Dr. Manning

Russell Napier

Character: Scotland Yard Supt. Davidson

Cyril Cusack

Character: Dr. Kelly

Frederick Piper

Character: Medwood Inspector Hayman

Karl Stepanek

Character: Dmitri Balinkev

Alfred Maron

Character: Ambulance Driver

John Welsh

Character: George White - the Gamekeeper

Olive Sloane

Character: Mrs. Lemmin - the Landlady