‘Big Bang Theory’ Cast on Life Lessons From Bob Newhart

TV's No. 1 comedy welcomes one of the small screen's most iconic comedic actors Thursday when Bob Newhart begins the first of what he hopes will be a recurring role on CBS' The Big Bang Theory.

Newhart makes his return to comedy playing Professor Proton, a childhood hero of both Leonard (Johnny Galecki) and Sheldon (Jim Parsons), whom the latter tracks down and invites over for a stroll down memory lane.

For Newhart, the comedy icon told The Hollywood Reporter that the experience was "like going back in time" to Stage 17, where he filmed both Newhart and The Bob Newhart Show. For the cast, however, the experience ranged from being "incomprehensible," a dream come true and a master class in comedic acting, with the six-time Emmy nominee receiving a standing ovation from the live studio audience.

The Hollywood Reporter hit the Burbank set to catch up with the cast and get the inside scoop on their experience with Newhart.

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Jim Parsons (Sheldon)
It was incomprehensible; you can't comprehend what it is you're doing. We've had some great people on this set but he was the first person that I had that feeling of, "I can't believe you're real." He's an icon, a person that you have in your mind or in your heart and they just don't seem real. His timing, delivery, demeanor -- and he brought the most positive energy and optimistic outlook to have around the set. I've heard whispers that he's coming back and I'm thrilled.

Johnny Galecki (Leonard)
He had a two-minute standing ovation from the live audience. Then the DJ starting playing the theme song from his old show and he started crying. I was standing next to him, so I started crying. It was very touching. The script metamorphosized during the week as they do and it really became art imitating life in that this is a hero of Leonard and Sheldon's and they have the opportunity to tell their childhood hero how much he means to them. We all got choked up because the episode became a real homage to not only Newhart but to all of the great comic legends that came before us and this show.

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Kaley Cuoco (Penny)
It was interesting watching him work from day one to shoot night -- it was like watching an education. I don't think he missed a beat. There were moments where I was sitting in the scene, staring at him, forgetting I was even in it because he just became that genius that we all know. I assumed he was going to play a scientist and I wouldn't be in any scenes with him but I was lucky to have gotten to be in the whole storyline with him. It was a dream come true.

Kunal Nayyar (Raj)
I moved to America in 1999 and didn't grow up with Bob Newhart. I knew the name, but when everyone was excited that he was going to be on the show, I Googled Bob Newhart and watched clips on YouTube and realized what good shows he was on. When he came on stage and everyone gave him a standing ovation at the table read, I didn't understand that moment. It didn't hit home to me until I realized that it was like if I was in Bollywood and a childhood favorite actor of mine came to The Big Bang Theory -- I would be standing up clapping, too.

Simon Helberg (Howard)
He was in a completely different storyline and I wanted to take him down with our dog storyline (laughs). Bob is an icon and you feel the presence -- it's so understated, relaxed and beautiful; especially seeing the way it came together filming. He's so subtle that there were so many other things going on that I noticed while the cameras were on him.

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Melissa Rauch (Bernadette)
I grew up watching him with my dad and used to listen to his stand-up album. I passed by his dressing room like five times before I went in. He was so lovely and I told him about how his album meant so much to me. We had a great conversation about stand-up and the live audience. I called my dad -- who is not an emotional man -- and heard his voice crack. I sent him a picture of Bob and I. It was so amazing to watch him in that scene with Jim. The two of them together, there's such a special feeling. When Bob came out for his bow, he made a beautiful little speech about being here and we all just had tears in our eyes. It was really beautiful.

Mayim Bialik (Amy)
I wasn't in that week but I did get to meet him when he came in to reshoot the tag. I spent many, many hours of my awkward teenage years watching Newhart and it was super exciting. I don't know that he knew who I was (laughs).

The Big Bang Theory airs Thursdays at 8 p.m. on CBS. Are you looking forward to seeing more of Professor Proton? Hit the comments below with your thoughts.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit

Lesley Goldberg