A television announcer reports the sighting of a red fireball around the world and suggests it’s coming to California. Nancy Archer (Allison Hayes), a wealthy but unstable woman with a drinking problem, is driving at night in on a desert road. A glowing sphere lands on the highway in front of her and she veers off the road. A huge creature reaches for her, but she escapes and runs back to town.

Nobody believes her as an alcoholic and a former mental patient. Her philandering husband Harry Archer (William Hudson) is busy with his latest girlfriend Honey Parker (Yvette Vickers). He hopes his wife will snap and end up back in the booby hatch so he can control her fifty-million-dollar estate. She volunteers to go back in if he finds nothing on the road. They find the alien sphere and the huge male figure. Harry shoots it to no effect and runs, leaving Nancy behind. She is later found delirious on the roof of her pool house and is sedated by her physician Doctor Cushing (Roy Gordon). He believes she was exposed to radiation.

Harry plans to inject her with a lethal dose of sedative, but when he sneaks into her room, he finds that she has grown to giant size. Doctor Cushing and Doctor Von Loeb (Otto Waldis), a specialist brought in, are stymied by her condition. They keep her in a morphine-induced coma and in chains while waiting for the authorities. Sheriff Dubbit (George Douglas) and the Hayes family Butler Jess (Ken Terrell) track huge footprints from the estate to the alien sphere. Inside, they find her diamond necklace and other giant diamonds, and they think it is a power source for the ship. The huge creature reappears and they run away.

Nancy awakens and breaks out of her restraints. She tears off the roof and, dressed in a kind of bikini made out of sheets, heads into town to get revenge on her husband. She rips the roof off the local bar and finds Honey, then drops a ceiling beam on her. Harry panics, grabs the deputy’s pistol and shoots her, to no avail. She picks up Harry and walks off with him. The Sheriff fires a shotgun which blows up a transformer, killing her. Harry is found dead in her hand.

The film was directed by Nathan H. Juran (or Nathan Hertz) and produced by Bernard Woolner from a screenplay by Mark Hanna. The music was scored by Ronald Stein. It was only 66 minutes long but lengthened with slow credits to 75 minutes for TV. There were plans for a sequel, but it never got past the script. A plan in 1979 came to nothing. In the mid-Eighties there was supposed to be a remake with Sybil Danning, but that didn’t happen either. It was finally remade in 1993 by HBO with Darryl Hannah starring and producing, directed by Christopher Guest. In 2011, Roger Corman produced Attack of the Fifty Foot Cheerleader, starring Jena Sims, Miss Georgia Teen.

The movie was shot in eight days for $89,000 and came in $10,000 under budget. The giant space alien is played by Michael Ross, who also played the bartender. Yvette Vickers’ dance was suggested by Frank Chase, who played Deputy Charlie. He was the brother of Barrie Chase and the dance was inspired by Rita Hayworth’s dance in Gilda (1946). The famous prize-winning poster for the film was designed by Roger Corman. Despite being a cheap piece of crap by some standards, Nathan Juran’s directing skills were praised. Yvette Vickers was nearly injured by falling debris. She died at age 82 in 2011, and her body was undiscovered for a year. Allison Hayes died at 46 from lead poisoning in the calcium pills she was taking.