Seven strangers, each with their own secrets, converge at the El Royale, a rundown hotel straddling the border between California and Nevada. Among them are a down-on-his-luck priest, Daniel Flynn; a soul singer named Darlene Sweet; a traveling salesman, Laramie Seymour Sullivan, who is actually an FBI agent; a young Southern woman, Emily Summerspring; her impressionable sister, Rose; and the hotel's lone employee, Miles Miller. The guests have little in common but their presence at the El Royale, where they hope to find solace or redemption. As night falls, they settle into their respective rooms, unaware that the hotel's dark past is about to intersect with their own hidden agendas.

As the evening progresses, each guest's backstory begins to unravel, revealing that nothing and no one is what they seem. The El Royale has lost its former glory, now harboring secret passageways and a two-way mirror that allows someone to spy on the guests from behind the walls. The characters' paths intertwine when they discover bags of cash hidden beneath the floorboards, igniting a chain of events marked by violence and betrayal. Under the surveillance of unknown eyes and with tension mounting among the strangers, their chance for redemption slips away as they are forced to confront the sinister forces both within and outside the hotel walls.