Plan 9 From Outer Space (1959)

The movie opens with a narration from a group of aliens who reveal that they are from "the ninth planet of outer space" (Pluto). They express concern about humanity's dangerous advancements, specifically their development of a "solarigizer" (a doomsday weapon). The aliens decide to implement Plan 9, a plan to resurrect the dead to scare humans into halting their destructive pursuits.

The first scene introduces Julie and Jeff Trent, a couple who witness a flying saucer hovering over their home. As the saucer disappears and reappears in different locations, the couple is left perplexed. Meanwhile, cemetery caretaker, Ghoul Man, and his wife, are visited by their deceased elderly relative, who has been resurrected and now acts strangely.

The next day, the Trents report their encounter with the flying saucer to the police. The police dismiss their claims, not taking them seriously. Meanwhile, at the cemetery, the risen dead continue to cause havoc and kill anyone they encounter.

Later, the police inspector, Daniel Clay, and his subordinate, Lieutenant Harper, investigate the strange events at the cemetery. They discover several freshly dug graves and are attacked by a resurrected corpse. However, the alien, Eros, intervenes and helps Clay destroy the creature using a small device that disintegrates matter.

Eros and his assistant, Tanna, take Clay to their spaceship to explain their mission. They inform him about the resurrection program to discourage humanity from using the solarigizer and mistakenly believe that the recently risen dead have been responsible for their failures. Clay tries to contact his superiors to share this information but finds that all communication channels have been jammed by the aliens.

Meanwhile, Jeff Trent's wife, Paula, gets kidnapped by the aliens to use her as leverage against humanity. Eros threatens to kill Paula if Clay doesn't cooperate. In a dramatic turn of events, Clay takes a gun and holds Eros hostage while attempting to release Paula. However, Eros effortlessly disarms Clay and captures him instead.

Tanna, who has formed a connection with Jeff Trent, helps him escape from the spaceship and brings him back to Earth. They decide to unite with other humans and attack the alien base. Using a carefully timed explosion, they hope to destroy the saucers and save Paula and Clay.

In the final act, the humans confront the aliens in an intense battle. The confrontation results in the destruction of the alien saucers and the death of Eros and Tanna. The resurrection program halts, and the images of fallen humanity are broadcasted to the stars to serve as a warning.

In the closing scene, the aliens, having witnessed the defeat of their plan, acknowledge humanity's resilience and capacity to change, vowing never to visit Earth again. The Trents and Lieutenant Harper reflect on the events with hope for a brighter future.