Tobor the Great

Charles Drake

Dr. Ralph Harrison

Karin Booth

Janice Roberts

Billy Chapin

Brian 'Gadge' Roberts

Taylor Holmes

Prof. Arnold Nordstrom

Steven Geray

The Foreign Spy-Chief

Henry Kulky

Paul (Spy Henchman)

Franz Roehn

Karl

Hal Baylor

Max (Spy Henchman)

William Schallert

Johnston - a Reporter

Lyle Talbot

An Admiral