In 1987 Chicago, the witty stripper Angie Pitarelli finds herself in a relentless rivalry with Sally Mewbourne, the leader of a group of religious protesters outside the Revealers adult bookstore. Their animosity flares as Angie begins her shift working as an exotic dancer in the store’s peepshow booth.
Suddenly, an otherworldly rift appears in the sky, heralding the apocalypse. As chaos erupts, people outside turn on each other. In the tumult, Ray, the store’s owner, gets caught up in the mayhem while trying to protect his establishment from the frightened protesters. In a horrifying twist, Angie watches helplessly as Ray meets a gruesome fate, leaving her trapped within her booth.
Among the madness, Sally becomes the sole survivor to enter Revealers. Despite their conflicting morals and beliefs, both women recognize the necessity of joining forces to escape. Their troubles escalate when Ray returns, now a zombie, attacking Sally. In a frantic moment, Angie creates a diversion, allowing Sally to defend herself by brutally beating Ray to death with a crowbar. Sally reciprocates the act of bravery by rescuing Angie from a monstrous, sentient tentacle creature that threatens her life.
Angie soon hears the anguished voice of her nephew David calling for help. What initially seems like a plea turns out to be the voice of Asmodeus, whom Sally identifies as the demon prince of lust and judgment. As they seek sanctuary, they discover the hidden tunnels beneath Revealers, which were once used as a speakeasy during Prohibition.
In the tunnels, the dynamic between Angie and Sally undergoes a transformation. As they share their stories, Sally starts to view Angie through a different lens, especially when Angie openly reminisces about becoming her nephew’s guardian. An unexpected friendship grows between the two as they learn to appreciate their differences. However, tensions rise again when Sally insists on taking a tunnel leading toward Saint Augustine’s Church, while Angie is eager to find David. This disagreement forces them apart temporarily but not for long; Angie ultimately returns to save Sally from a swarm of slithering creatures.
Sally's faith is deeply challenged when she realizes that the snakes were after her, not Angie, despite her attempts to lead a virtuous life. In a moment of vulnerability, Angie uncovers Sally’s concealed feelings, revealing her envy and suppressed identity as a lesbian. Angie clarifies that the demons are drawn to her not because of her sexuality but because of her unwillingness to confront her own truths.
In a climactic battle, Asmodeus launches an assault against them. Through a series of intense confrontations, Angie and Sally unite to defeat the demon, showcasing their newfound bond. They arrive at mysterious underground doors believed to lead to the church. As unease sets in, Sally senses the world outside may have ended, yet Angie's spirit remains undeterred. She confidently takes Sally's hand, and they step through the doors together, where the lights flicker ominously, echoing demonic laughter, and the fourth trumpet from the Book of Revelations sounds. The camera pulls back, revealing a world above consumed by the chaos of the end times.
