Big Bang Theory Season 12 Brings Back Fan-Favorites Bob Newhart & Keith Carradine

Sheldon and Professor Proton in The Big Bang Theory

The Big Bang Theory season 12 will feature some familiar faces, like Bob Newhart (Arthur Jeffries/Professor Proton) and Keith Carradine (Wyatt - Penny's dad).  It's an understatement to say that the cancellation of the geek-focused series came as a surprise to a lot of fans, considering that even after 10 years, the show remains a ratings hit for CBS. But rumor has it that the decision stemmed from Jim Parsons' (Sheldon) decision to walk away from the series, despite potentially pocketing $50 million if he had signed on for two more years.

CBS is pulling out all the stops for the final season of their juggernaut sitcom, which is set to begin in just two weeks. But before The Big Bang Theory's last hurrah even premieres, new details continue to emerge with regard to what fans can specifically look forward to in the show's final episodes, including some notable guest appearances.

Related: Big Bang Theory Final Season Trailer Reveals New Footage

TV Line reports that Bob Newhart will be back on The Big Bang Theory to reprise his role of Professor Proton. This will be the sixth guest appearance by the actor in the hit sitcom, after his first appearance in season 6's "The Proton Resurgence." Newhart's return isn't really a surprise, considering that executive producer Steve Holland previously expressed the show's intention to feature some of its most popular guests from throughout the years, including the 89-year-old comedy legend. A separate report from TV Line reveals that aside from Newhart, Keith Carradine will also appear in The Big Bang Theory's upcoming final season, reprising his role as Penny's father, Wyatt.

Penny and Wyatt in The Big Bang Theory

No specific details were given with regard to either guest appearance, but fans of the sitcom know that Professor Proton's presence could mean that there's another huge life moment coming for Sheldon. Since his death during season 7's “The Proton Transmogrification,” he's continued to appear occasionally in the form of an apparition (similar to a Force Ghost in Star Wars), almost always when Sheldon is struggling with something. Proton's most notable appearances after he passed on include him helping Sheldon decide whether to see The Force Awakens on its premiere night or spend Amy's birthday with her (Sheldon picked the latter), and helping Sheldon adjust to the disturbing fact that frenemy Wil Wheaton had become the new Professor Proton.

As for Penny's dad, perhaps his appearance has something to do with the overdue reveal of her last name before she married Leonard and became Penny Hofstadter. For the past 11 seasons, The Big Bang Theory got away with not confirming Penny's surname, but since the show is finally wrapping up - with no word about any potential spin-offs that might continue Leonard and Penny's story - fans naturally want to have this mystery resolved, and what better way to do it than by having her dad say it himself.

More: Should The Big Bang Theory Get Another Spinoff?

The Big Bang Theory season 12 premieres September 24 on CBS.

Source: TV LineTV Line

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