In the year 1969, a group of unlikely individuals converge at the enigmatic El Royale hotel, each harboring their own secrets. Among them is the dubious Catholic priest, Daniel Flynn (played by Jeff Bridges), who is actually a robber disguising himself to blend in. Alongside him is the captivating singer Darlene Sweet (portrayed by Cynthia Erivo), along with the charming salesman, Laramie Seymour Sullivan (played by Jon Hamm), who is revealed to be an undercover FBI agent, operating under the alias Dwight Broadbeck.
As they check into the honeymoon suite, Sullivan uncovers a hidden passage that leads to a series of rooms equipped with one-way mirrors and a 16mm camera setup monitoring the guests. Intrigued, he catches glimpses of Daniel Flynn rummaging through the floorboards and witnesses a shocking scene—a kidnapping by the witty and sarcastic Emily Summerspring (brought to life by Dakota Johnson), who is seen tying up her younger sister, Rose (played by Cailee Spaeny).
Sullivan's directive from his superior, Hoover, is not to intervene in the kidnapping situation and to sabotage the guests' vehicles to thwart any escape plans. Amidst the drama, Flynn attempts to charm Sweet into dinner, but his ulterior motives become evident when he tries to drug her drink. However, with a swift and daring move, she seizes a bottle and knocks him out, fleeing from the chaos of the hotel.
Miles Miller, the hotel's sole employee and a former sniper from the Vietnam War, discovers Flynn and reveals the unsettling truth about the hotel's secretive management filming the guests. In a twist of fate, Flynn, who is actually a criminal by the name of Donald O'Kelly, pressures Miles into surrendering a damning film reel he has stashed away.
As the night unfurls, both Emily and Rose confront Miles about the surveillance operation, unveiling Emily's dangerous past with a cult led by the sinister Billy Lee (played by Chris Hemsworth). Just as they plan to escape, Billy and his followers storm in, holding everyone hostage, interested in the money Flynn and Sweet have found and the incriminating footage.
In an intense game of roulette orchestrated by Billy, the stakes become deadly as Emily is brutally killed. In the ensuing chaos—a fire igniting in the hotel—an unlikely hero emerges. Miles, invigorated by the memory of his past, retrieves a gun and confronts the cult, ultimately killing Billy and his minions. However, in a heartbreaking twist, Rose fatally stabs Miles but is then shot by O'Kelly, who is caught in a web of remorse and guilt.
As the night wanes, Sweet and O'Kelly manage to escape with the hidden cash, while Sweet destroys the damaging film in flames. They depart the flaming remnants of the bizarre hotel, leaving behind a night filled with chaos, betrayal, and unexpected alliances.
Later, Sweet takes to the stage in Reno, performing confidently as O'Kelly watches on, proud of their tumultuous journey—a stark contrast to their harrowing experiences within the El Royale.
