LA's Buzziest Immersive Horror-Theater Production Just Opened. We Went Behind the Scenes.

During the day, the massive Boyle Heights warehouse that's the home of The Tension Experience -- the just-opened, horror-themed immersive theater experience that's attempting to do for interactive performance in LA what Sleep No More has done for the genre in NY -- is about as nondescript as warehouses come. The whole thing is hidden on a city block in plain view behind a wrought-iron door, near power-lines and a pot dispensary scenting up the whole neighborhood, just around the corner from a slew of massive trucks loading and unloading whatever it is massive trucks unload.

Inside is another story, though: Darren Bousman, the guy behind a bunch of the Saw movies, has created a world tinged with occult-style horror, and is inviting patrons to figure out the mystery behind a sacrificial cult that's taking applications for new victims (the backstory is so convincing that when the website went up, some people thought it was an actual cult -- and applied to join).

In advance of its opening for Halloween season (though the expectation is that, unlike many "haunts," it will continue indefinitely) -- Bousman let us go behind the scenes to see how it all goes down.

The whole concept of interactive theater -- essentially, a performance that unfolds with audience members interacting with performers, and the lines between them sometimes becoming so thin it's impossible to see -- is not entirely a new one in LA: Delusion, which at this point has become a Fall staple that sells out immediately after dates are announced, is a special-effects-filled show with the audience occasionally performing a task or dragged out of a group, only to appear later in an unexpected location. The recent The Day Shall Declare It sort of operated as moving theater-in-the-round, with a bar operated by performers as its centerpiece and final destination.

But no show in LA has had the full immersion of genre-definers like Sleep No More, which puts patrons in masks to make them anonymous before breaking them up from their groups, or London's Secret Cinema, which literally recreates entire movie sets and scenes with the audience able to interact with characters (for instance, they recently made a full-sized set of Tatooine for an Empire Strikes Back-themed show -- and you could have drinks with Uncle Owen and Aunt Beru in their sand-hut.

The Tension Experience, the organizers explain to me in one of the the first rooms participants will see -- what appears to be an old-age home's living room, with puzzles, senior citizens who stare at you for minutes on, and notes hidden in mirrors and furtively passed by caregivers -- was set up to be a more psychological version of this immersion. In fact, long before the public performances, they were setting up the story with a series of insider-y mind-fucks: phone numbers hidden in messages from the writers led participants to psych tests, where they sat across from an interviewer who asked them deep secrets (these questions, including everything from "do you think animals can feel" to "how often do you masturbate," have made their way into both online questionnaires and the show itself).

"Movies used to be an escape and TV used to be an escape," says producer Gordon Bijelonic, sitting on a vintage couch in the "waiting room." "I say used to because there was a time we would go to the movie theaters, would not take our phones with us. Today you're watching the movie but you're not present. You're watching it but you're responding to emails. You're watching the movie but you're responding to your Facebook posts. But what I love about this [immersive theater experience] is that you really do disappear in a fantasy. You are fully immersed for two hours. You need to be present."

That means cell phones (and, really, any sense of your personal possessions) are literally taken away at the beginning of the show, you'll likely be split up from the people you came in with -- and the full commitment to that personal experience is key for both the performers and the attendees.

A tour can only give a hint of what to expect from the show: even in the light, hallways like this one have a bit of freak-show appeal -- but at night, in the dark, they can serve as confusing and frightening halls, with participants occasionally forced to wear hoods over their heads and smell odd smells and taste odd flavors for a true multi-sensory experience. Actors often give choices to participants -- and depending on your answer, you can end up anywhere from...

... a tiny box of a room surrounded by static-blaring TVs to...

... a classroom full of walls with the rantings of a madperson (Anoch? Who's that? Maybe someone important?)...

... to an interview room that's starkly -- alarmingly -- all white.

In fact, the compound the Tension Experience is in has dozens of rooms -- each equipped with a camera, and each of which is being watched as participants are led through experiences that veer from existential dilemmas ("what's the meaning of life?") to horrific experiences ("is that guy that was just shot... dead?") The director and writers are following along the whole time because the timing is crucial: if any of the dozens of actors (many of whom occupy familiar horror tropes, like wise-or-is-he?-old-man and stringy-haired Jesus figure) are late to their cue, it can literally throw the entire experience off course.

In that regard, Tension is nothing like traditional horror maze: there are no monsters jumping out in rubber masks, and it's not as surreal or torture-y as some recent additions to the LA nightmare-scape, like Blackout. "There's nothing really scary," says Bousman. "That's not what this is. It requires you to be present, it requires you to step outside your comfort zone. It requires you to do things you might not normally do."

It's also the first step in a multi-pronged plan -- what they're calling Tension Experience: Ascension is the team's first show, but they're talking about making it into a movie, followed by a sequel show, if it's successful. And, from the amount of care they've put into it -- and the market they're grabbing a foothold in -- it's clear that they have reason to be confident it will be.

"[LA doesn't] have theater the way New York City has Broadway or Off Broadway or Off Off Off Broadway," says Bijelonic. "Now that you have all these veteran [immersive theater shows] that have paved the road here in LA -- being [early adopters] Delusion, being Blackout, being Alone, there's definitely a place for it, for theater goers. For someone who wants to live it and breathe it and participate. And that's what I find fascinating."

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