After a young man is killed in an unexplored subterranean cavern and his girlfriend driven mad by something she saw there, a track found at the scene cannot be identified with any known animal and thus a scientific expedition is launched to find out just what it is that is living there.

Genres

Cast

José Elías Moreno

Profesor Díaz

Kitty de Hoyos

Hilda Ramírez

Columba Domínguez

Laura Ponce

Javier Solís

Dr. Manuel Ríos

Carmen Molina

Julia

Carlos Nieto

Novio de Julia

Armando Acosta

Gerente de gruta (uncredited)

Roberto Meyer

Padre de Julia (uncredited)

Inés Murillo

Turista (uncredited)