While flying their atom ship through space, a crew of humanoid Venusians collides with an asteroid. Made from a frozen mist, the planetoid doesn't destroy the spaceship, but begins to fast-freezes its occupants. Managing to reach the controls, a crewman pilots the vessel to earth, to Salt Lake City, Utah. Though encased in ice, he struggles to the nearest building, where scientists just happen to be experimenting with gamma radiation. Pelted by the rays, the Venusian is thawed and revived.
The police find his comrades dead and assume that he has killed them. Running off, the extraterrestrial turns into ice once again and finds that everything he touches freezes, including a lake that he dives into to elude the police. Later, saving the town from a flood, the alien eventually wins the trust of humankind, learns that he can control his freezing power with an atomic ray gun, and becomes a potent force against crime as the Sub-Zero Man.
Later he got an Eskimo sidekick named Freezum.
In addition to being able to freeze objects by simply looking at them, he is safe from bullets which "crumble to bits" when fired at him.