Harold Jensen
The Doctor
Orson Stillman Mayor
Jess Parkinson
Charles Sabin
Joe Klein
Thomas Bellairs
Saucer Man
Matt Hays
Archie
The Mailman
Ship Passenger
Hunter
Cavanaugh
Moore
Dignitary
Stage Performer
E. Lansing Ray - Editor, St. Louis Globe Democrat (uncredited)
Dr. Borg
Mr. Brown (uncredited)
Mr. Lansing
Company Lawyer (uncredited)
Prof. Ulbrecht Olinger
Simmons
Count Molda / Joseph Stalin
Mr. Forbes (uncredited)
George
Dr. Howard Culver
Capt. Arwin
Maigret
Don Morell, Sales