Characters played by George Murphy
Inspector James 'Jim' Belden
Characters played by Finlay Currie
Professor Albert Kafer
Characters played by Virginia Gilmore
Millie Zalenko aka Teresa Henning
Characters played by Karel Stepanek
Alexi Laschenkov aka Gregory Anders
Characters played by Louisa Horton
Elaine Wilben
Characters played by Peter Capell
Chris Zalenko aka Gino
Characters played by Bruno Wick
Luther Danzig
Characters played by Jack Manning
Melvin Foss aka Vincent
Characters played by Karl Weber
Charlie Reynolds
Characters played by Robert A. Dunn
Dr. Wincott
Characters played by Vilma Kurer
Rita Foss
Characters played by Michael Garrett
Michael Dorndoff aka Frank Torrance
Characters played by Lotte Palfi Andor
Anna Kafer
Characters played by Ernest Graves
Robert Martin
Characters played by Robert Carroll
Boldany
Characters played by Wolfgang Zilzer
August Helmuth
Characters played by George Roy Hill
Nicholas Wilben
Characters played by Bradford Hatton
Harry Mason
Characters played by Rosemary Pettit
Mrs. Martin
Characters played by Eva Condon
Landlady
Characters played by Steve Mitchell
Samson
Characters played by Ann Thomas
Philadelphia Suspect
Characters played by John Farrell
Taxi Driver
Characters played by Nancy Hale
Mrs. Belden
Characters played by J. Edgar Hoover
Self
Characters played by Suzanne Moulton
Sherry Belden
Characters played by Westbrook Van Voorhis
Narrator
Characters played by Mary Young
Old Lady