John Merivale as Dr. John Fielding

Didi Sullivan as Ellen Fielding

Gérard Herter as Max Gunther

Daniela Rocca as Linda

Vittorio André as Prof. Rodriguez

Daniele Vargas as Bob

Nerio Bernardi as Police Inspector

Giacomo Rossi Stuart as Prof. Rodriguez's Assistant

Gail Pearl as Indian Dancer

Tom Felleghy as Astronomo

Arturo Dominici as Nieto

Mario Bava as Mexican at police station (uncredited)

Renzo Palmer as Narrator (voice)

Leslie Daniels as Prof. John Fielding (voice)

Renato De Carmine as Prof. John Fielding (voice)

Stefano Sibaldi as Max Gunther (voice)

Michele Malaspina as Prof. Rodriguez (voice)

Rolf Tasna as Bob (voice)