Stuart Fails to Save the Universe has already reunited fans with one familiar face, with Kunal Nayyar reprising his role as Raj Koothrappali in the premiere episode. The second episode also delivers a major surprise, bringing back another beloved original Big Bang Theory cast member in a completely unexpected way.
The Big Bang Theory followed physicists Sheldon Cooper (Jim Parsons) and Leonard Hofstadter (Johnny Galecki), along with their close-knit group of friends. Aspiring actress Penny (Kaley Cuoco) moved in across the hall from Sheldon and Leonard, quickly became the heart of the group, helping her socially awkward neighbors step outside their comfort zones.
The HBO Max spinoff, Stuart Fails to Save the Universe, shifts the focus to comic book store owner Stuart Bloom (Kevin Sussman), who embarks on a multiverse adventure with Bert (Brian Posehn), Barry Kripke (John Ross Bowie) and Denise (Lauren Lapkus). Along the way, the group encounters alternate versions of familiar Big Bang Theory characters — and one of the biggest surprises arrives in Episode 2.
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Titled “Spoiler: Zack’s in This One,” the episode picks up after Stuart, Bert and Kripke escape the post-apocalyptic Pasadena introduced in the premiere and stumble into what initially appears to be a much friendlier universe. That illusion doesn’t last long.
The trio quickly discovers they’re wearing neck devices that shock them every time they argue or behave aggressively, ultimately sending them to a 30-month reeducation program designed to eliminate conflict. After completing the program, they’re unexpectedly abducted and taken to an abandoned warehouse.
Once their hoods are removed, they’re greeted by a very familiar face: Cuoco‘s Penny.
But this isn’t the Penny fans remember.
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Instead of the aspiring actress-turned-pharmaceutical sales rep from The Big Bang Theory, this version sports brunette hair and leads a resistance movement against an AI-controlled world alongside her ex-boyfriend Zack, reprised by Brian Thomas Smith. To snap Stuart, Bert and Kripke out of their relentless positivity, she literally slaps each of them across the face to “deprogram” them.
It’s exactly the kind of surprise creators Chuck Lorre, Bill Prady and Zak Penn hoped longtime fans would enjoy.
For Prady, 66, reinventing familiar characters across different realities was one of the most rewarding parts of revisiting the Big Bang Theory universe.
“One of the great things about this is that because every universe has its own history, when we encounter characters, they have a different past than they had in the Big Bang Theory universe,” he says.
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Lorre, 73, says bringing back Cuoco, 40, also meant giving Penny an entirely new life, one that looks nothing like the character fans first met in Apartment 4B.
“I think at the end of the day, we handled some of those guest appearances beautifully in ways you don’t anticipate,” Lorre tells. “Because we’re in an alternate universe, a different reality, Penny becomes someone else. She’s still Penny, but she has an entirely different background. She never worked at the Cheesecake Factory, never met Leonard. She’s a leader of a revolutionary guerrilla group, and she’s not averse to violence.”
Lorre adds with a laugh, “I think it is a wonderful thing to see Kaley Cuoco smacking the s— out of our hero.”
Stuart Fails to Save the Universe drops new episodes Thursdays at 9 p.m. ET on HBO Max.