'The Big Bang Theory': [SPOILER] Becomes Professor Proton

with a new actor, he jumps at the chance to become the new Professor Proton. Unfortunately, his [...]

(Photo: CBS / Michael Yarish)

During tonight's episode of The Big Bang Theory Sheldon (Jim Parsons) hoped to become the new Professor Proton. However, Wil Wheaton (himself, as usual) got the part!

When Sheldon hears of plans to replace the late Arthur Jeffries (Bob Newhart) with a new actor, he jumps at the chance to become the new Professor Proton. Unfortunately, his nemesis Wheaton also wants the job.

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Amy helps Sheldon audition for the role, even filming his audition tape. Unfortunately, Sheldon doesn't have any ideas for non-life threatening experiments for children. Amy also tried to get Leonard and Penny tell Sheldon how terrible his audition tape was.

Sheldon asks Wheaton to be his acting coach, only to learn that Wheaton got the part!

Although Arthur isn't alive any longer, he still appeared in the episode as a ghost in Sheldon's dream. He delivered some Jedi-esque advice, as Sheldon imagined him as a Force ghost from Star Wars. Sheldon is angry about Wheaton getting the part. The only advice ghost Arthur has to offer is that most people don't like to remember the day they met Sheldon.

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Sheldon told Wheaton he shouldn't take the part because he's not a scientist. Wheaton tries to convince Sheldon that he'll work very hard to inspire a new generation of scientists just like Arthur did.

Meanwhile, Bernadette and Howard's daughter said her first word - "Mama!" Unfortunately, she called Penny "mama."

Professor Proton is the character who inspired Sheldon and Leonard to become scientists in the first place. Newhart has also appeared as the character on Young Sheldon.