John Merivale

Dr. John Fielding

Didi Sullivan

Ellen Fielding

Gérard Herter

Max Gunther

Daniela Rocca

Linda

Vittorio André

Prof. Rodriguez

Daniele Vargas

Bob

Nerio Bernardi

Police Inspector

Giacomo Rossi Stuart

Prof. Rodriguez's Assistant

Gail Pearl

Indian Dancer

Tom Felleghy

Astronomo

Arturo Dominici

Nieto

Mario Bava

Mexican at police station (uncredited)

Renzo Palmer

Narrator (voice)

Leslie Daniels

Prof. John Fielding (voice)

Renato De Carmine

Prof. John Fielding (voice)

Stefano Sibaldi

Max Gunther (voice)

Michele Malaspina

Prof. Rodriguez (voice)

Rolf Tasna

Bob (voice)