In the late 1800's, Boris Karloff has discovered a way to use nuclear power. He creates a beam weapon and blows up a big rock. Outer space aliens are scared and one alien who looks a lot like James Cameron with a big fake nose only this one isn't fake lands and brings other aliens who take over the bodies of Karloff and his assistant. The assistant is a Jack the Ripper style killer who has done a few nasty murders which have riled the townsfolk. The body-snatched bodies become radioactive and start killing flowers and other stuff (but don't die themselves) and some stuff happens and in the end Karloff destroys the beam weapon equipment (and his lab and house), then the aliens leave and warn us that if anyone ever does it again there will be trouble.

Arácnea's residents have been desperately searching for a source of food to save the life of their queen (a big spider). Earth is chosen, since human brains are apparently like health food for alien spiders.

Romance, stolen jewels and sitcom humor on a bus-trip from Tijuana to Guadalajara.

Maria San Carlos, the only daughter of a wealthy landowner, is betrothed to Escobar, a General in the Mexican Revolution, but she does not love him. Escobar sends a mixed gang of Americans and Mexicans to capture her and bring her to him. Complications ensue when an American cowboy, who had been hitching a ride with Maria's entourage and has his gold stolen by the gang, pursues them across the desert.

Dr. Castellanos is saved from bankruptcy.

A group of juvenile delinquents live a violent life in the infamous slums of Mexico City; among them Pedro, whose morality is gradually corrupted and destroyed by the others.