Villain(s)  Three-eyed human beast

Actor(s):  Richard Denning, Lori Nelson, Adele Jergens, Mike Connors

Brief Description  Day the World Ended is a 1955 independent black-and-white post-apocalyptic science fiction horror film directed and produced by Roger Corman. Set in the aftermath of a devastating nuclear war, the 79-minute film explores how a disparate group of survivors interact, clash, and face radioactive horrors in an isolated mountain valley.

Plot:
The movie begins with a stark opening text claiming the story starts with "THE END". Stock footage of a nuclear test plays while future NBC news anchor Chet Huntley delivers a grim narration: "Total Destruction Day" has arrived, and humanity has nearly annihilated itself in a global nuclear war. Amidst the atomic haze, a survivalist named Jim Maddison and his daughter, Louise, hole up in a well-provisioned, fortified home situated inside a deep, protected valley in the California hills. Due to unique atmospheric currents and surrounding rock formations, the canyon shields them from the deadly surrounding radioactive fallout.

Jim reluctantly shelters the newcomers, warning them that their food and water are strictly rationed to outlast the fallout. Tension immediately spikes inside the house. Tony schemes to steal the supplies, kill the other men, and take Louise for himself. Meanwhile, Radek refuses to eat the clean food, driven by a strange, radiation-induced psychological mutation to crave contaminated flesh. The internal strife is compounded by an external horror. A terrifying, telepathic three-eyed mutant monster—mutated by atomic radiation—begins stalking the canyon.

The beast exhibits a telepathic hold over Louise, drawing her toward the radiation-soaked wasteland. As resources dwindle and the mutant closes in, the group collapses into violence. Tony stabs Ruby and tries to seize power, but Rick fights him off. In the climax, the mutant attacks the compound and grabs Louise. Before it can escape, a sudden downpour of pure rain—which cleanses the atmosphere of the radioactive fallout—begins to fall. Because the mutant's biological structure is completely tied to atomic energy, the clean rainwater burns it away like acid, destroying it. With the air safely cleared, the remaining survivors—Rick, Louise, and Pete—leave the canyon behind to trek outward and rebuild civilization.