Roddy McDowall
Eric Kardin
Kristine Miller
Marlina
Harry Lauter
Franz
Rand Brooks
Captain Giorg Nicholoff
Byron Foulger
Professor Kardin
Murray Alper
Nicholas
Marc Krah
Double Agent on Train
Kate Drain Lawson
Mrs. Krechow
Michael Vallon
Old Man on Train Station
Effie Laird
Scrubwoman
Glen Vernon
Student
Fred Kohler Jr.
Soldier
Bob Peoples
First Lieutenant (uncredited)
Gil Perkins
First Organizer (uncredited)
Fred Krone
First Student (uncredited)