Barry, a mechanic and family man, finds his life abruptly upended when an apocalyptic event turns most of humanity into zombie-like creatures. The transformations seem to be triggered by contact with the atmosphere, and those affected quickly become mindless, bloodthirsty monsters. Barry loses his wife and daughter in the chaos and sets out on a desperate quest to find his sister, Brooke. Brooke, meanwhile, has her own struggles as she is captured by a deranged military doctor conducting horrifying experiments on survivors and the infected.

Along the way, Barry teams up with Benny, a fellow survivor who has also lost his loved ones to the plague. Together, they navigate the perilous, zombie-ridden landscape in a makeshift, armored vehicle that runs on zombie blood—a discovery that gives them a fighting chance. They face numerous threats from both the living and the dead as they attempt to reach Brooke and evade the relentless military forces. Their journey is fraught with danger, forcing them to rely on each other and their resourcefulness to stay alive. As they close in on Brooke's location, the situation becomes increasingly dire, pushing them to the brink of survival.