Jay Baruchel travels to Los Angeles to visit his old friend, the Canadian actor Seth Rogen, who soon invites him to a housewarming party hosted by James Franco. At first, Jay feels out of place amid the crowded, loud gathering, so Seth steps outside to take a breather and they end up wandering to a nearby 7-Eleven for cigarettes. In that ordinary moment, the world changes: a sudden rapture sweeps through the area, and Seth and Jay rush back to Franco’s house, only to discover the party appears untouched by the phenomenon.
What follows is a jagged sequence of shocks. An earthquake rattles the city, and the crowd spills into the yard to witness a dramatic sinkhole opening in Franco’s front lawn. The spectacle turns deadly as several celebrities and partygoers die in the chaos. The survivors—led by Franco, Seth, Jay, Jonah Hill, and Craig Robinson—bar doors, hoard supplies, and fortify the house, trying to ride out the catastrophe as news broadcasts confirm that Los Angeles has been largely wrecked.
As dawn approaches, tension rises. Danny McBride, who had crashed the party and fallen asleep during the night, wakes to find the situation far more dire than anyone anticipated. His stubborn disbelief clashes with the others’ warning, even as a man outside is decapitated by an unseen terror. The group’s dynamics fray: Jay and Seth drift toward estrangement, while others question whether the disaster marks an apocalyptic omen. Emma Watson briefly reappears, only to bolt with what remains of their drinks after misinterpreting overheard conversations, fearing the group intends harm toward her.
Robinson makes a perilous attempt to fetch water from Franco’s cellar, only to encounter a strange being outside. This encounter lends credence to Jay’s increasingly persistent apocalyptic theory. Jay and Seth manage to pry open a hidden water source after digging through the floor, but McBride, still playing by his own rules, drains most of what they find and is ultimately expelled from the house. In a tense exchange, McBride reveals that Jay was in town two months earlier but chose a hotel stay over bunking with Seth, highlighting the fractures in their friendship.
The darkness deepens when Hill, filled with fear and hostility, is briefly possessed and prays for Jay’s death. An exorcism attempt escalates the danger: a candle is knocked over, a fierce blaze erupts, and the fire consumes Hill and, soon after, the house. The group contemplates a move to Franco’s Malibu home, but their path is blocked by a demon guarding Franco’s car. In a devastating twist, Robinson volunteers to sacrifice himself to enable the others to escape, and his selflessness earns him a place in Heaven.
On their way toward Malibu, the trio encounters a band of cannibals led by McBride, who has abducted a companion, Channing Tatum. Franco makes a final, reckless bid to reach safety, offering himself up in a calculated act of sacrifice. A blue beam appears, seemingly pulling him toward Heaven, but Franco’s taunts provoke McBride to cruelly reject his offer, and Franco is eaten alive while Rogen and Baruchel narrowly escape. The situation worsens as they come face-to-face with Satan, who attempts to devour them.
In a moment of hard-won reconciliation, Baruchel apologizes to Seth for their earlier conflicts, and a celestial beam finally strikes. Baruchel ascends toward Heaven, but his very presence on the ascent path disrupts the moment, forcing Seth to stay behind. A second beam then targets Satan, inadvertently castrating him as Rogen and Baruchel cling to each other in a final, poignant moment of camaraderie.
The surviving pair reach Heaven, where they are reunited with Robinson. There, they learn that any wish may come true. Baruchel’s wish lands on a playful note—he asks for the Backstreet Boys—and the fantasy world delivers: the group bursts into their hit “Everybody (Backstreet’s Back),” and everyone dances in celebration as a sense of peace settles over the afterlife.
