The bass of the music vibrates through the Italian marble floors. You're holding a glass of vintage champagne, surrounded by your four best friends—Mark, Leo, Chloe, and Sam—in the grandest mansion you've ever seen.

But something is wrong. Every time you move, you hear the faint 'whir-click' of a security camera in the ceiling rotating to follow your head. The staff who let you in have vanished. The shadows in the corners of the cavernous rooms seem to be leaning inward. You get a sudden, sickening jolt of déjà vu, as if you've stood in this exact spot, feeling this exact fear, a hundred times before.

The music suddenly cuts to a screeching halt. The heavy steel-reinforced front doors hiss shut with a sound like a guillotine.

A woman's voice, smooth and mocking, crackles over the speakers: "The check-in process is complete. Now, let's see which of you is worth keeping..."