Sheldon, played by Jim Parsons, right, and Leonard hire Professor Proton, played by guest star Bob Newhart, left, to perform, on "The Big Bang Theory."
Sheldon, played by Jim Parsons, right, and Leonard hire Professor Proton, played by guest star Bob Newhart, left, to perform, on "The Big Bang Theory." CBS ENTERTAINMENT
Sheldon, played by Jim Parsons, right, and Leonard hire Professor Proton, played by guest star Bob Newhart, left, to perform, on "The Big Bang Theory." CBS ENTERTAINMENT