Ja-young and her friends decide to shoot a video titled “Spirit Summoning That Tells You Everything” for a YouTube contest with a cash prize. Initially planning to stage the whole event as fiction, they begin filming in the water tank of an abandoned building. However, prompted by Ja-young’s suggestion, they attempt a real séance. Ja-young hopes to uncover clues about her older sister, who went missing when they were children — but what begins as a playful ritual soon spirals into a terrifying experience none of them can handle. What starts out as curiosity and fun gradually transforms into a nightmare. The séance, conducted in a confined and claustrophobic space, is rendered with chilling realism, adhering to the conventions of classic horror. The film skillfully builds tension through the occult element of spirit summoning, while also revealing the slow unraveling of friendships and long-buried secrets, maintaining strong dramatic momentum throughout. Standing apart from typical teen horror, the film boasts high genre polish and gripping performances from actors like Kim Yerim and Lee Chanhyeong. With its immersive terror that makes viewers feel as if they're part of the ritual — and a finale that defies all expectations — it leaves a lasting impression.