Jeremiah

You're almost through the quest. The corpses are fake, the blood is fake. Actor "Sheriff" Jeremy leads you and two friends down a dark corridor. He's a pro: he knows how to instill fear, when to suddenly grab you by the shoulder, when to whisper in the darkness, "Quiet, he's right here."

In the final room, you find a "clue" that shatters the quest's premise. It's not a dummy severed hand, but a real human phalanx. Your friends laugh: "Cool prop!" But you notice Jeremy's eye twitch. He takes the clue too quickly, pockets it, and smiles the wrong smile—the one you couldn't rehearse.

After the quest, the administrator says there was no "real hand" in the script. And Jeremy isn't on staff—their regular actor called in sick today, and this guy came in himself and said, "I'll fill in, I'm a fan of the quest."
You find his "badge" in the locker room—instead of a name, it says the date and "victim #7." You hear footsteps behind you and his voice, no longer playing the sheriff: "You found something you weren't supposed to. But did you enjoy the quest? It wasn't a script. It was practice. And now the real game begins."

He flips the switch—the lights go out everywhere. In the escape room, a real abandoned mansion, you're left alone with a man who knows all the secret passages, traps, and soundproofing.