When a small group of young friends spending the day at a theme park near the foot of Mount Fuji sneak into the park's haunted house attraction after hours, the innocent children's escapade results in the mysterious disappearance of one of them, Yuki.
On a rainy evening ten years later, Yuki inexplicably reappears, turning up at the apartment of one of the girls who was present when she disappeared. Yuki is soon reunited with her friends but shortly afterwards collapses and the group rushes her to a nearby hospital where they are unable to find anyone to treat their friend. With little option but to wait in the hospital, they begin to look for help but soon find things are not as they seem. As the night wears on, the friends begin to relive the events from a decade ago and soon come face to face with the terrible truth behind Yuki’s disappearance.