In a dark and cramped space, horror novelist Lee Soo-hee (played by Park Han-byeol), unemployed college graduate Choi Ji-ho (played by Kim Gi-seok), and high school sophomore Park In-jung (played by Park Jin-joo) wake up from unconsciousness. They do not know each other and are unaware of how they ended up here. After their initial panic, the three of them try to find a way out of the basement and enter a nearby house. The house is well-equipped and has a strong sense of daily life, yet there is no sign of anyone else around. They try to escape from this forest, but can never find the exit. Meanwhile, strange events begin to unfold around them, and an inexplicable panic grips each of their hearts, as a murderer seems to be lurking in the shadows, ready to take their lives at any moment. Under mutual reminders, their lost memories gradually resurface, but it seems to reveal a terrifying truth that is hard to face...