Volcanic activity frees giant scorpions from the earth who wreak havoc in the rural countryside and eventually threaten Mexico City.

Richard Denning
as Hank Scott

Mara Corday
as Teresa Alvarez

Carlos Rivas
as Artur Ramos

Mario Navarro
as Juanito

Carlos Múzquiz
as Dr. Velazco

Pascual García Peña
as José de la Cruz

Fanny Schiller
as Florentina

Arturo Martínez
as Major Cosio

Pedro Galván
as Father Delgado

José Chávez
as Train conductor (uncredited)