Seeking a fresh start and a cross-country adventure, the Carter family piles into their vintage Airstream trailer, led by retired
police detective Bob and his wife, Ethel. Accompanied by their children Lynn, Brenda, and Bobby, along with Lynn's husband Doug and their baby, the group embarks on a doomed journey through the scorching Nevada desert. Despite warnings from a grizzled gas station attendant about a desolate atomic testing zone, Bob arrogantly ignores the advice and steers the vehicle off the beaten path, hoping to make up time. Disaster strikes when the trailer blows a tire in the
middle of nowhere, stranding them under the blistering sun.As night falls, the true horror of their situation unfolds. Unbeknownst to the family, the surrounding hills are inhabited by a vicious, inbred clan of cannibalistic mutants, born from the devastating genetic fallout of past nuclear tests. Led by the monstrous Papa Jupiter, the feral ghouls—including the towering Pluto and the sadistic Mars—watch the stranded travelers like predators stalking helpless prey. Motivated by a desperate need for fresh meat and supplies, the mutants launch a coordinated, brutal assault on the camp.Chaos erupts as the savages murder Bob in a horrifying display of violence, leaving the remaining family members terrorized and isolated. Ethel and Lynn are brutally killed, while Brenda is subjected to harrowing trauma at the hands of the feral attackers. Left with no choice but to tap into their most primal instincts for survival, the meek suburbanites must transform into ruthless warriors. Doug, pushed past his pacifist limits, sets out on a frantic mission of vengeance and rescue alongside the family's fiercely protective German Shepherds.In a bloody, adrenaline-fueled climax, Doug and the surviving siblings wage a relentless guerrilla war against the mutants in their own subterranean caves. Utilizing makeshift weapons and sheer fury, they systematically hunt down the remaining cannibals. The harrowing ordeal leaves the surviving Carters profoundly scarred, forever altered by the horrific depths of human and mutant savagery they confronted in the desolate wasteland.