Lord John Roxton
Jennifer Holmes (as Jill St.John)
Ed Malone
Prof. George Edward Challenger
Manuel Gomez
Prof. Summerlee
David Holmes
Costa
Native Girl
Burton White
Man at Airport (uncredited)
Airport Attendant (uncredited)
Prof. Waldron (uncredited)
French Member of Zoological Institute Forum (uncredited)
Indian Chief (uncredited)
British Member of Zoological Institute Forum (uncredited)
Guest at Zoological Institute Forum (uncredited)
Member of Zoological Institute Forum (uncredited)
Reporter (uncredited)
TV Announcer (uncredited)
Stuart Holmes (uncredited)
Man at Airport / Guest at Zoological Institute Forum (uncredited)
Zoological Institute Professor on Stage (uncredited)
German Member of Zoological Institute Forum (uncredited)
Italian Member of Zoological Institute Forum (uncredited)
Guest at Zoological Institute Form (uncredited)
Reporter at Airport (uncredited)
BBC Field Reporter Ted Bottomley (uncredited)