The Black Scorpion

After the earthquake, Dr. Hank Scott and Dr. Arturo Ramos are dispatched to San Lorenzo to study the crisis. En route they encounter a destroyed house, a totaled police car, and a dead policeman, along with an abandoned infant. This discovery sets the tone for the village's desperate situation.

The two scientists take the infant to San Lorenzo and entrust him to friends of the missing parents. They are welcomed by Father Delgado, the village priest, who explains the mounting fear and the villagers' belief in a demon bull.

Father Delgado reveals that the property damage and livestock killings may be connected to the strange phenomena. The villagers press him for divine help as the crisis grows, adding to the tension in the village.

Major Cosio arrives to coordinate disaster relief alongside the scientists. Hank Scott meets Teresa Alvarez, a local rancher, and begins to fall in love while befriending the young boy Juanito.

As the volcano erupts anew, the disappearances and deaths are revealed to be caused by giant prehistoric scorpions. The creatures begin slaughtering livestock and terrorizing the village.

The scorpions attack San Lorenzo and kill a crew of telephone repairmen. The Mexican military is unable to harm them, forcing the town to fend for itself.

The next morning the scorpions retreat to their underground lair. Entomologist Dr. Velasco asks Hank and Arturo to scout the cavern and assess whether poison gas could reach the space.

Inside the cavern, Hank and Arturo encounter giant worms and spiders while observing the scorpions. They discover the lethal weakness: scorpions kill each other by striking a small white spot on their throats.

Returning to the surface, Velasco explains the cavern is too vast for adequate gas filling, so the only option is to seal the entrance with dynamite. Hank worries about other entrances, but Velasco insists all sightings point to this source.

Days later, the scorpions reappear to attack a train and claim more victims. The clash exposes internal struggles among the creatures as the largest one eliminates rivals and heads toward Mexico City.

Hank and Arturo devise a plan to lure the lead scorpion to a stadium with a truckload of meat. The military provides a distraction long enough to prepare a kill.

A spear attached to an electrified cable is aimed at the throat's white spot, but the shot misses. The power remains on, and the gunman is fatally electrocuted during a reload while trying to salvage the attack.

Hank regains the initiative and fires the spear again, finally slaying the last scorpion. The threat to San Lorenzo is ended, bringing relief to the townspeople and the ranchers.

The danger is over, and the village begins to recover with the memory of the crisis. Hank's romance with Teresa deepens as peace returns to San Lorenzo.