At Silver Lake's old Bethany Presbyterian Church on a recent Thursday night, a gathering of well turned out Angelinos murmur with nervous anticipation.

A sudden hush falls over the room as a hooded woman with a ghastly pallor appears and loudly calls out, “Will the Death group please gather here by the bar?”

People immediately examine wristbands labeled with words like “Pestilence” and “Famine” until ten audience members meekly gather as directed and are promptly led away like proverbial lambs to the slaughter.

“It still boggles my mind that people pay to get scared,” says Jon Braver, the creator, writer and director of this audience-interactive Halloween horror hit, Delusion: Masque of Mortality, a 45-minute dramatic thrill ride of post-apocalyptic survival.

Credit: Courtesy of Haunted Play

Credit: Courtesy of Haunted Play

Masque of Mortality is the third incarnation of Braver's Delusion series, which debuted in 2011 to instant acclaim among fright aficionados for its fully scripted scenarios, professional actors, vividly atmospheric production designs and dazzling stunt work.

But what mostly distinguishes Delusion from the scores of immersive tours that sprout each October like unseasonal crab grass is the dizzying and labyrinthine level of audience interactivity that Braver engineers into each new show.

Masque of Mortality is no exception. From the moment they are led into the first chamber, audience members find themselves trapped in a nightmarish hospital in a pandemic-ravaged city that has reduced the populace into slavering zombies. And the hospital's menacing staff of “Plague Doctors” is looking for new subjects for their grisly experiments.

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To escape that fate, the audience is guided by a resistance group that proceeds to hector, push and prompt them from room to room, through secret passages, past wards of predatory, pustule-pocked patients, down corridors of gruesomely infected ghouls and into dark sub-cellars patrolled by ax-wielding lab assistants.

Braver has been fascinated by horror since his student days in Chicago, where he studied music and eventually graduated with a degree in guitar. “I had a crazy, ridiculous passion for Halloween and theater and old films like The Shining and The Omen and stuff like that,” he says, “so I always thought that one day I should create some kind of a play, like a moving play that would have [audiences] perform the characters in a moving horror story.”

Instead of pursuing music, an interest in gymnastics somehow led Braver to Los Angeles and a ten-year career as a successful Hollywood stunt man. In 2011, he hung up his stunt spurs and founded the company Haunted Play to realize his dream of producing interactive horror.

Credit: Courtesy of Haunted Play

Credit: Courtesy of Haunted Play

The spine of every Delusion plot is adapted from first-person video role-playing games. That means gathering the clues that will lead to the key that will unlock the door that will deliver the audience from peril.

But Braver's love for horror movies is evident throughout much of Mask of Mortality. Production designer Christopher Reed's sets and Ronen Mintz's lighting draw from a film vocabulary that ranges from finely detailed cinematic realism to German expressionism as one progresses deeper into both the building's interior and the dark heart of the story.

The evening's most inspired moments effectively mimic the carefully composed and limiting camera angles of the psychological horror masters, with many scenes playing just out of direct sightline. Such as when the audience is forced to cower in a large closet and can only get fragmentary glimpses of the menace lurking just outside the door. Or when spectators must dive for cover underneath the beds of a demented dormitory and watch the scene play out through a narrow gap between the draping bed clothes and the floor.

That conceit of limited and varying subjective points of view is echoed by what has become Delusion's most celebrated signature — the diverging plot twists that split individual audience members from their tour group into side-plots that require them to perform specific tasks. It's an experience that can be unsettling for both spectator and performer alike.

In last year's show, which was staged in a decrepit mansion on the edge of the Historic West Adams district, one such side-plot required a volunteer to sneak into a bathroom and remove a key from around the neck of a character who had apparently fallen asleep in her tub. Once the volunteer stepped inside, however, the door would slam shut and lock, and that person would be “kidnapped” for several scenes before rejoining the group.

Credit: Courtesy of Haunted Play

Credit: Courtesy of Haunted Play

On one night, Braver recalls, “There was a woman who got captured, and when the door slammed shut behind her and she was alone away from the safety of her friends, she just flipped out and started running around in circles like a chicken with her head cut off, screaming 'Help! Help! I wanna get out of here! I wanna get away!'” Security quickly intervened and calmed her enough to put the woman back into the play.

On another occasion, the script called for an audience volunteer to dance with an actress in order to retrieve a ritual knife prop from the character. “One guy who was slightly buzzed slipped in,” remembers Braver, “and he grabbed the actress and started dancing with her, but holding her hand really tight, and it was really painful for her. And he kind of grabbed the knife and was like jokingly threatening [her with it]. We threw the security guard in there and … whisked him away, like, incredibly fast. It was amazing. It was like he was there and he was gone. He was just joking and playing and really getting into it, but at that point we needed to pull him out.”

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In fact, audiences are under constant observation by production security and Braver himself — the security for safety reasons and Braver to monitor the dramatic impact of his creation. “People are kind of funny to watch,” he reflects. “I hide behind the walls and just watch them do their thing, and it's kind of cool to see how they react. … That's kind of what this thing is to me also, a big social experiment.”

If so, it's also a chemistry experiment. Since the audience also plays characters in Delusion, the mix of temperament and personalities turns out to be a key factor in both the quality and uniqueness of each performance.

“You never know who's going to come,” Braver explains. “The hardest part of this whole thing is that … sometimes people just hang out in the back and don't do anything. They're not really participating. But if you let yourself go in this show — and really let yourself go — then you'll have the experience that I hope people will have. It's such a role of the dice.”

Delusion: Mask of Mortality plays through November 23.

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