Stuart Fails To Save The Universe Episode 2 Sneak Peek: Bert And Kripke's Search For Leonard And Sheldon Leads To Ramona Nowitzki (Exclusive)

The search for Drs. Leonard Hofstadter and Sheldon Cooper in "Stuart Fails to Save the Universe" Episode 2 leads Bert Kibbler and Barry Kripke to Caltech — and to the desk of one Ms. Ramona Nowitzki.

TVLine has an exclusive sneak peek from Episode 2 of "The Big Bang Theory" spin-off "Stuart Fails to Save the Universe," featuring Riki Lindhome reprising her role as the woman who once tried to steal Sheldon away from Amy. In this alternate reality, however, everyone has an artificial intelligence chip implanted in their necks, and even the slightest hint of negativity or outrage prompts the AI to administer a painful shock to anyone whose behavior is deemed inappropriate. That's bad news for Kripke, especially when Ramona — who, in this universe, is a Caltech receptionist — refuses to let him and Bert see Leonard and Sheldon without an appointment.

Lindhome appeared in three episodes of "The Big Bang Theory," beginning with Season 2's "The Cooper-Nowitzki Theorem," which introduced Ramona as a Caltech graduate student with an obsessive crush on Sheldon. After attempting to micromanage every aspect of his life — then suggesting they share credit for his latest scientific breakthrough — Ramona was swiftly shown the door.

Eight years later, Ramona, now Dr. Nowitzki, resurfaced in the Season 10 finale, "The Long Distance Dissonance," and made another play for Sheldon while Amy was away at Princeton. But after Ramona planted a kiss on him, Sheldon immediately flew to New Jersey and proposed to Amy instead.

Lindhome made her third and final appearance in the Season 11 premiere, "The Proposal Proposal," when the guys gleefully rubbed Ramona's nose in Sheldon's engagement.

Riki Lindhome is the latest "Big Bang Theory" franchise veteran to guest-star on "Stuart Fails to Save the Universe." She follows Penn and Teller, who both appeared on "Young Sheldon" — while Teller also recurred on "The Big Bang Theory" as Amy's father, Larry — and original cast member Kunal Nayyar, who made a surprise return as Raj in Episode 1.

Alas, this version of Raj, who inhabited a post-apocalyptic wasteland, had been imprisoned by Grand Caliph Barry Kripke after losing his wife to a giant moth. Kripke later killed Raj in an effort to prevent Stuart from saving the universe. (The series premiere averaged a TVLine reader grade of "B.")

In addition to Lindhome, HBO Max has already confirmed that Christine Baranski — who recurred for 11 out of 12 seasons of "Big Bang" as Leonard's mother Beverly, and whose return to the franchise was previously spoiled in a trailer — guest-stars in Episode 2 (premiering Thursday, July 30 at 9 p.m. ET).