Inside 'Terrarium': The Horror Film Shot by Actors on an Empty Stage

There are actors on the set of "Terrarium" — but no set. On a late Wednesday morning in September at Hollywood's BLT Studios, director Jason Zada's cast performed against black tarps and bare walls on a well-lit soundstage, with 26 crew members hidden from view and nearly everything else, save the humans themselves, set to be generated with AI.

"Terrarium" is a found-footage style horror film about four teenagers who take shelter underground after an unspecified catastrophic event. Three characters — Tim, Devin and Reese — appear on camera; the fourth, Lila, is represented by the camera itself. The production team calls the method an AI-hybrid production: a team of 15 to 20 AI "artists" generates the locations and props around the human actors. The convenience store the characters explore? AI. The eerie underground tunnel? AI. Even the group's positioning is assembled by AI, with Zada shooting each actor against an individual camera and compositing them into shared scenes.

The film was announced in May after Amazon's AI on the Lot event. It is a co-production between Zada's AI-driven entertainment studio Secret Level and the AI production platform Artlist, which is financing it. Steven Schneider, whose credits include "Paranormal Activity," "Insidious" and last year's "The Long Walk," serves as executive producer. The cast includes Jake Busey ("Stranger Things," "Starship Troopers"), "Love Island USA" season seven personality Ace Greene, and newcomers Kylee Levien and Austin Willard. Zada aimed to complete the project the following week; the film is still seeking a distributor.

Zada, whose last feature was 2016's "The Forest" — roughly $40 million gross against a reported $10 million budget — says the microbudget film will look like a movie with a $40 million budget. He and the producers declined to disclose the actual cost. He calls the method "the future of how you make films."

"I think if we were on a larger budget, maybe some of this would be shot on location," Zada says. "But then again, every time I think about that, I go, 'I shot my last movie. We were in a forest for a long time, getting eaten by bugs and spending a week doing night shoots and having to sleep for a few hours during the day.' I don't miss that."

On set, the old pitfalls persist. Busey, playing the villain, repeatedly missed his "You guys coming?" line and took an unprompted break mid-scene. In the green room afterward, still in costume on his final day of shooting, he described the challenge of acting against nothing. "It's far more difficult as far as the acting portion goes because you're really going back to kindergarten," Busey says. "You're really going back to cowboys and Indians running around the backyard, and you really are those characters."

Busey distinguishes "Terrarium" from the industry's worst-case AI scenarios. "The big fear for us actors, when it comes to hearing the term 'AI movie,' the big fear is that you'll have companies that'll do a full body scan, and then they will entirely complete you doing a performance that you weren't even there for, and that's the scary thing," he says. "This film is not that."

Lead Kylee Levien, 17, plays Lila, with much of the film shot from her point of view. She spent much of her contract negotiation ensuring her performance remained intact, not wanting it to be a product of "AI impersonating me." "Learning the AI is working with that, but not with what's going on with our facials or behind our eyes or our acting… knowing that boundary was set was very reassuring to me," she says.

Secret Level head of narrative and producer Christina Lee Storm says the production worked extensively under SAG-AFTRA's new rules on digital replicas and AI across the four-month shoot. "The markers are really transparency and consent," Storm says. "There's always going to be bad actors, and that's where like something like the No FAKES Act needs to sort of get solidified and all that by the government."

Schneider, who helped produce "Late Night with the Devil" — a film that drew outrage over its use of AI, which he says he learned of after completion — now insists on disclosure. "There's no excuse for not being above board with our use of AI," he says. "Omission is sort of just as bad as intentional deceit."

Zada dismisses critics of the technology as trading in "hearsay." "To me, hating AI for filming is the same thing as hating CGI," he says. "Every film will eventually have some form of AI in it."

When the cast and crew finally watched a two-minute behind-the-scenes reel — their composites stitched into shared rooms, Greene's character's father bursting into flames — faces lit up. "That's the roughest you'll ever see," Zada told them. "If that's the worst it's gonna look, just think about the possibility."

Outside, the crew was shooting a scene inside a real parked sedan, one of the film's few physical props. Whatever the future of AI filmmaking holds, "Terrarium" suggests it will still include at least one actual car.