‘Stuart Fails to Save the Universe’ Cast Breaks Down ‘Really Weird’ Finale on ‘Big Bang Theory’ Stage

The Stuart Fails to Save the Universe finale picks up with Stuart (Kevin Sussman) and the gang seemingly landing nowhere — only to discover they’re somehow back at the comic book store, where Kyle (Ryan Cartwright) is waiting. He has also learned what they’re really up against: a swirling, conscious “ball of s**t” that has existed since before the Big Bang and absolutely hates Stuart and his friends. In fact, consciousness itself caused the Big Bang, something the entity apparently remains pretty bitter about. Warning: Spoilers ahead for Stuart Fails to Save the Universe Season 1 finale!

Stuart’s device opened a crack in reality that allowed the entity to pull the plug on every universe, essentially. Now it has trapped the gang inside the comic book to prevent Stuart from undoing the damage he caused. That means Stuart is technically responsible for destroying everything that ever was, ever will be, and ever could be.

Things only get stranger when Stuart suddenly finds himself in his bedroom with no memory of how he got there. Denise (Lauren Lapkus) is celebrating her birthday, but everyone begins behaving like they’re trapped in a conventional sitcom. Even stranger, Kripke (John Ross Bowie) can hear a laugh track nobody else can.

Looking through the comic books, Kripke realizes that all of their previous adventures are there, including the cow stomach, the paradise universe, the world where Gary dies, and the nuthouse. There’s even an underwater adventure in which everyone has gills — except that one hasn’t happened yet.

As the laugh track begins driving Kripke crazy, Bert (Brian Posehn) starts hearing it, too, while Stuart briefly catches a glimpse of something beyond their world: an actual television set. Kripke finally puts everything together. They aren’t just inside another universe — they’re inside a sitcom. Denise’s birthday storyline is merely the B-story distracting them from the main plot.

That realization sends the finale fully through the fourth wall. Stuart literally wanders beyond it after telling Denise he loves her, and the gang eventually finds themselves on the actual Warner Bros. lot at Stage 25, watching the actors who play them take their bows in front of an audience.

Making the moment even more surreal for the cast was the fact that they really were back on familiar ground.

“We were literally back on the same stage that we shot Big Bang on, when we shot those live shoots and we had that audience,” Brian Posehn revealed to TV Insider. “We had the same warm-up guy from the old show.”

That familiar face was Mark Sweet, who spent years warming up The Big Bang Theory studio audience and gets to appear as himself in the finale. “Mark Sweet, who was the audience warm-up guy and plays himself on Episode 10, which was awesome, because talk about a guy that needs credit,” said John Ross Bowie. “Talk about a guy who is long overdue for his applause.”

But returning to the stage was only part of what made the experience so strange. As the actors played themselves, they also found themselves surrounded by stand-ins dressed to look like them.

“We were standing there going, ‘This is f**king weird,’” laughed Posehn. “It’s really weird. There’s no other reaction to it. And having the audience there! And then to have stand-ins playing ourselves, dressed like us — because we had stand-ins playing Bert and Kripke, but to have stand-ins being Brian and John, was super weird.”

For Kevin Sussman, the layers became even more complicated during the curtain call. He was playing himself, but also had to approach the moment differently because, within the fictional version of the show, Stuart was its star.

“The shooting of just the curtain call, because in the fiction of the show, Stuart is the main guy in that, I did a curtain call in a way that I, Kevin Sussman, wouldn’t have done, say, on Big Bang Theory. I wouldn’t have done a big flourish with it. So even that was weirdly odd for me to do. It felt weird to be that guy, that version of you,” said Sussman.

With their reality completely shattered, the gang leaves the studio and heads into the still of Burbank looking for answers, passing posters of alt-reality sitcoms, including Young Leonard and Two and a Half Women.

Meanwhile, back at the comic book store, the mysterious entity finally confronts Kyle. And it isn’t happy, telling him simply: “I gave you one job.”

Stuart Fails to Save the Universe, Season 1, Now Streaming, HBO Max