Bob Newhart to guest star once again as Professor Proton on 'The Big Bang Theory'

Bob Newhart has twice appeared on the hit CBS sitcom The Big Bang Theory as Professor Proton, the scientist on television who served as an idol for Leonard and Sheldon as children. And Newhart is set to return for another encore performance, according to a new report.

TVLine first reported exclusively that Newhart has booked another guest-starring appearance on The Big Bang Theory as Professor Proton. This will be his third appearance on the show after his debut in Season 6 and his return earlier in Season 7. The site reports that the circumstances of the character's reintroduction are unknown, nor does the site specify a date or episode for his return.

Newhart most recently appeared in a November episode entitled "The Proton Displacement." Here's an excerpt from MStars' review of the episode:

"Once again, Newhart delivered the goods with a deadpan delivery so dry that I'm surprised sand didn't come out of his mouth when he spoke. The characters on The Big Bang Theory each have their own idiosyncrasies and quirks that are played up to ridiculous levels sometimes, most notably Sheldon. In this episode alone, Sheldon annoyed people constantly by repeatedly asking them to say he was annoying.

The genius of Newhart's performance in this episode is that he plays the straight man to all the insanity going on around him. The look on his face alone was enough to convey the "what the hell am I doing here with these wackos?" sense. He even asked the question we've all been thinking for more than six years: Why is Leonard friends with Sheldon?"

You can read the full review here.

Check back with MStars for more on this story as it develops, but for now, give us your thoughts! Are you excited to see Newhart return? Let us know in the comments below.