Two intelligent aliens, with the intention of taking over the human race, disguise themselves as black crystalline rocks and lie in wait in a geologist's laboratory. One doctor, who has a metal-plate in his skull, can hear the aliens in their communication with each other. The aliens, realising they can be heard, set out to kill him.
Thinking he is going mad, the doctor goes on a vacation to Mexico, but unbeknown to him another scientist, controlled by the rocks, is pursuing him.
Some astronauts are captured by alien beings, called Ebonites, and taken to the planet Ebon as prisoners. After being interrogated and tortured in turn, it appears that one of their number has turned traitor.
A cleaning lady, working at the Norco Energy Research Commission, sweeps up a strange black mass. Once in the vacuum it feeds off the electric motor. It soon grows ever more powerful and can consume anyone or anything at a touch. Dr Block finds a way to contain the entity.
While conducting research into magnetic fields, scientist Ian Russell, drops his pencil into the mechanism. He puts his hand through a strong magnetic field, to extricate the pencil, just as the polarities are reversed. When he retrieves his hand, he is horrified to discover that it has been reversed. He now has two right hands.
What sort of strange void have they discovered, and what would happen if a whole person was to enter such a borderland?
In a lake in a South American dictatorship, there is reputed to be a creature. John Dexter heads a team of explorers in search of the legendary creature. When they manage to capture it, John Dexter plans to take it back to the U.S., but he is opposed by Juan Mercurio the country's dictator. The creature, meanwhile, is hatching plans of its own.
The military has isolated a deserted town in the Californian desert in preparation for the arrival of a spacecraft from the planet Zanti. It is a ship containing the planet Zanti's undesirables. Unfortunately there is a jailbreak!
The Department of Neo-Kinematics has a machine that can break down matter and convert it into electrical waves so that it can be transmitted across vast distances and then reassembled. Inhabitants of the planet Chromo are interested in making an exchange, one of the members of their species for one of ours, in the interest of science. But the chromite that is sent is really on a mission to test the Earth's environment to see if it is fit for a mass invasion.
Two Martians try to understand what causes human beings to commit murder. Equipped with a device that can control time, they examine a passion crime in a hotel's lobby.