‘Stuart Fails to Save the Universe’ episode 2 features four ‘Big Bang Theory’ stars, including a fan-favorite

Episode 2 of ‘Stuart Fails to Save the Universe’ brings back four franchise veterans as Stuart’s group escapes an AI-controlled alternate universe.
A still from 'Stuart Fails to Save the Universe' (Cover Image Source: HBO Max)
A still from 'Stuart Fails to Save the Universe' (Cover Image Source: HBO Max)

Episode 2 of 'Stuart Fails to Save the Universe' features four returning actors from 'The Big Bang Theory,' but their appearances are alternate-universe versions that do not follow the original sitcom's continuity. Kaley Cuoco returns as Penny, Brian Thomas Smith appears as Zack, Riki Lindhome plays another version of Ramona Nowitzki, and Christine Baranski appears as herself instead of Leonard’s mother, Beverly Hofstadter. The episode places Stuart, Bert, and Kripke in an alternate universe controlled by an AI that uses implanted devices and electric shocks to keep people calm and obedient. Penny and Zack lead the resistance, trying to bring down that system.

The four appearances continue the spinoff’s use of legacy actors in alternate versions of familiar roles. Episode 1 brought back Kunal Nayyar as Raj before Kripke killed that universe’s version of the character. None of the returning characters are portrayed as coming from the original sitcom's universe. Their lives and relationships were shaped by the alternate reality that Stuart's group entered.

Riki Lindhome in ‘Stuart Fails To Save the Universe’ episode 2 (Image source: HBO)
Riki Lindhome in ‘Stuart Fails To Save the Universe’ episode 2 (Image source: HBO)

Lindhome is the first returning guest star seen in the episode. Her version of Ramona works as a receptionist at Caltech, where Stuart, Bert, and Kripke arrive after entering the alternate universe. When their behavior leads to punishment, they are sent to a 30-month re-education program. Baranski then appears in an introductory video as herself, delivering propaganda for the AI regime rather than reprising Beverly.

The episode’s biggest return comes after the trio is released from re-education. Cuoco’s Penny leads the resistance, while Smith’s Zack serves as her second-in-command. Penny tries to deprogram Stuart, Bert, and Kripke by slapping them, then orders their deaths after learning they do not know how to defeat the AI. The three survive when the regime launches a drone attack and incapacitates Penny, Zack, and the other resistance members.

Penny’s partnership with Zack does not change her marriage to Leonard in the original ‘Big Bang Theory’ timeline. Co-creator Bill Prady told Deadline, “Because that’s what happened in that universe, we don’t know what Leonard is doing in that universe.” He added, “Every universe gives every character a completely different history. There’s no continuity because they lived a different life, they lived in a different world.” Chuck Lorre also noted, “There was no Cheesecake Factory in her life.”

The creators chose Penny to lead the resistance because the role reverses what viewers might expect while drawing on traits she showed in the original series. Lorre told TVLine that “The fun of this series is the unlikely character assuming a new role.” Prady said, “Penny was always the most capable member of the original group. If you had to actually get something done, you were probably better off if Penny was in charge of it.” Lorre added, “There was always that Nebraska, get-the-job-done quality to her.”

Christine Baranski in ‘Stuart Fails To Save the Universe’ episode 2 (Image via HBO)
Christine Baranski in ‘Stuart Fails To Save the Universe’ episode 2 (Image via HBO)

Stuart, Bert, Kripke, and Denise escape the AI-controlled universe by using the quantum interference device built by Leonard, Sheldon, and Howard. Stuart also brings Denise’s AI counterpart with them after rescuing her from her marriage to Gary. Their next jump takes them to a universe where magic is real, and scientists are burned at the stake. The episode ends with Bert moments away from execution, setting up the group’s next attempt to survive and continue their journey across the multiverse. New episodes of ‘Stuart Fails to Save the Universe’ stream exclusively on HBO Max. 

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