Sheldon hires Professor Proton (guest star Bob Newhart) to come to his apartment on The Big Bang Theory. "The Proton Resurgence" is the 22nd episode of the show's sixth season.
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The Big Bang Theory Season 6 Episode 22 Quotes

Howard: Why don't you put her in a kennel?
Raj: Why don't you put your mother in a home?
Howard: To be honest, she'd do better in the kennel.

Leonard: It was pretty cool.
Penny: Aw, so cute when you use the word "cool" wrong. Like when kids say "pasghetti."