Michael Rennie
Lord John Roxton
Acting
Jill St. John
Jennifer Holmes
Acting
David Hedison
Ed Malone
Acting
Claude Rains
Prof. George Edward Challenger
Acting
Fernando Lamas
Manuel Gomez
Acting
Richard Haydn
Prof. Summerlee
Acting
Ray Stricklyn
David Holmes
Acting
Jay Novello
Costa
Acting
Vitina Marcus
Native Girl
Acting
Ian Wolfe
Burton White
Acting
Colin Campbell
Prof. Waldron (uncredited)
Acting
John Graham
Stuart Holmes (uncredited)
Acting
Larry Chance
Indian Chief (uncredited)
Acting
Bert Stevens
Reporter at Airport (uncredited)
Acting
Al Bain
Man at Airport (uncredited)
Acting
Bess Flowers
Guest at Zoological Institute Forum (uncredited)
Acting
Kenner G. Kemp
Guest at Zoological Institute Forum (uncredited)
Acting
Cosmo Sardo
Guest at Zoological Institute Forum (uncredited)
Acting
Murray Pollack
Guest at Zoological Institute Forum (uncredited)
Acting