John Mylong

as Archive Footage (Robot Monster)

as Colonel Duval

as Dr. Hofer

as The Professor

as Kaiser Wilhelm II (uncredited)

as Martin Krafft

as Colonel Henry Bouquet

as Druhar (uncredited)

as Mr. Duchin

as Nicholas Bederaux, Sr. (uncredited)

as John Stuart

as Captain of Submarine

as Herr Gosting

as Herr Koenig

as Peter Vantine / Carl Dudley

as Staff Officer (uncredited)

as Submarine Commander

as Jan

as Ernst Steinhauer

as Kroll