Horizon Villa. A two-story building that appears to be a wealthy, antique, and luxurious villa at a glance, but its true identity is a supernatural disaster rooted in B-grade slasher movies. Grade: Brain-type. Surrounded by mountains and remote wilderness, any attempt to leave results in a natural disaster 'coincidentally' striking the person or causing a fatal accident. The phone lines are also dead due to heavy rain.

At regular intervals, it sets a condition for the villains who enter the disaster: 'The last survivor can take one thing they desire from here.' Initially, all seven people try to find a way out together while avoiding reality, but as time passes, they become aggressive toward each other, ending in [CENSORED].

When the Disaster Management Bureau, a government-affiliated organization, distributes cassette tapes to selected villains to punish them, the tapes lead them to the villa. Disposing of those villains was the duty of Ryu Jaegwan, an agent working for the Bureau.