The Deadly Spawn

Two campers witness a meteor crash nearby and investigate the strange rock that has fallen. A bizarre lifeform emerges from the meteor and ambushes them, swallowing them whole. The campers' disappearance signals the arrival of an alien danger that will soon threaten the nearby town.

Sam goes downstairs in the storm to check the basement for flooding, armed with a flashlight and concern. The creature lurking in the basement attacks him and feeds, leaving no chance to warn Barb. The family begins to realize something deadly is happening inside their own home.

Barb descends into the basement to search for Sam and is quickly killed by the same monster. The home becomes a perilous trap as the creature continues to hunt within the walls. The threat now looms over Pete and Charles in the upper rooms.

Uncle Herb, a psychologist, conducts a brief session with Charles to ease his curiosity about macabre topics. Pete is busy with plans for a study date with Ellen, Frankie, and Kathy. The family piece of normal life begins to fracture as danger grows.

An electrician comes to check a circuit breaker, and Charles, in a moment of mischief, corners him with a costume and slips to the basement. He discovers slug-like creatures feasting on the electrician's remains, guarded by a much larger mother monster. Using his discovery, Charles realizes the creatures react to sound and decides to stay silent to survive.

Ellen and Frankie discover one of the tadpole creatures dead on the way to the house and conclude it's unlike any Earth animal. Frankie hypothesizes an alien origin, but Pete remains skeptical and dismisses the idea.

At Bunny's house, Aunt Millie arrives for luncheon with her retired friends, unaware that spawn have infested the residence. The creatures reveal themselves, attacking, and the women fight back and manage to escape in Millie's car.

Back at the main house, Pete, Ellen, and Frankie seek out Uncle Herb for guidance only to find him being devoured by the spawn. The teenagers barricade themselves in Charles's bedroom as the adult monster stalks them upstairs.

Charles devises a distraction by turning on a radio, which lures the adult creature away, but it eats the radio and triggers an electrical fire. The trio pulls Kathy into the bedroom to save her as the monster closes in.

The monster breaches the door and kills Ellen by biting her head off, then throws her body from a window. Pete flees to another room, then climbs to the attic as Frankie and Kathy race upstairs, leaving Ellen behind.

Charles crafts a plan to blow up the monster using a prop head stuffed with flash powder wired to an outlet. He enters the attic to lure the beast, but the fuse is too short to reach the outlet. A spawned creature sacrifices itself by stepping into the monster's path and gets eaten, allowing Charles to ignite the powder.

With the adult monster destroyed, a city-wide hunt begins, and townspeople burn the spawn remains in a desperate cleanup. Pete, Millie, and Charles await help as police secure the area.

A patrolman on guard hears a distant rumble and looks toward the hill beside the house as it lifts, revealing a fully grown spawn waiting to emerge. The sense of victory dissolves into dread as the threat seems far from over.