Tunnel of Torment
A recent excavation has found the Universal Backlot Tunnel to be filled with corpses. Under the road, in the walls, in the roof, there are corpses everywhere. Police suspect that it's the work of John Melvin, a serial killer that may have helped create the tunnel decades ago, but has died recently. Enter the tunnel and experience John's afterlife - an eternity of torment at the hands of his victims.
The Backlot Tunnel, while often used as a scarezone, is interesting. There can be no setpieces, as they could interfere with the daily work at Universal Studios - and we all know that we can't interrupt the movie-making process. So, instead of ToXXXic Tunnel (Which would probably set expectations rather... naughty), I propose a scarezone set around ghosts. The area is black-lit, with glowing decals featuring cracks, the larger ones often showing skeletons. Scaracters wander about, painted to glow under the lights and with markings showing how they were killed. The music would either be metal or Figure's work. (REDRUM, Child's Play, and Micheal Myer's Dead would all be awesome - but possibly thematically inappropriate and profane. Universal has only dropped a single goshdarn fuckword, or so I've heard, despite Knott's using Manic Depresso so many years ago uncensored.)
John Melvin: Two guys, looking like Tor Johnson after being thrown out of a prison with no food for a few weeks, covered with electric scars. He stands outside either entrance, anxiously pacing.
Baseball Players: Two guys wearing baseball uniforms, with visible bruises on their face and arms. They carry baseball bats.
Decayed: 2 ladies wearing two-piece bikinis. Too bad their skin's rotted off, leaving nothing but faces and bones. They wield knives.
Construction Workers: Two guys wearing construction uniforms. One has a pipe through his eye, the other through his cap and skull. They can carry a wrench or a pipe.
Farmers: Two farmers. Throats were slashed. They carry scythes.
Teachers: Two female teachers dressed like old-timey school teachers. Will rather scold than attack, but don't make them bring out the rulers.