Alberto Medina is a famous composer whose car breaks down while he is on a trip. While looking for help, he finds the Valverdes' house and is welcomed in by Emilia, the mother of the family, who is known for taking in tramps.

California, 1847. The territory is about to be incorporated into the United States. Parker, the new governor, is a cruel man who believes that the time has come to get rich regardless of the means, but he will soon find a mysterious opponent driven to end his tyranny.

Resurrected by his grandson, a diabolical scientist with an unquenchable thirst for blood goes on a rampage. (A revision of the Mexican horror film LA MARCA DEL MUERTE, considerably edited and with 20 minutes of new American-made footage.)

Tourists visiting the pyramids in Mexico experience a string of deaths and disappearances while staying at a nearby hotel. Police investigators Fernando and Cornado are assigned to the case and attempt to solve the mystery with the help of reporter (and girlfriend of Fernando) Veronica and the wrestler Santo.