Thursday on TV: Bob Newhart visits the boys on "Big Bang Theory"
TV icon Bob Newhart returns to his old stomping grounds - a CBS sitcom - when he appears on this week's episode of The Big Bang Theory (7 p.m., CBS/Ch. 2).
He guest stars as Professor Proton, the star of a kids' show that Sheldon (Jim Parsons) and Leonard (Johnny Galecki) loved when they were kids. And word is that Newhart may be back next season.Elsewhere on TV ...Community (7 p.m., NBC/Ch. 5): Abed is convinced that members of the study group were destined to meet.American Idol (7 p.m., Fox/Ch. 13): Another contestant is eliminated.The Vampire Diaries (7 p.m., CW/Ch. 30): Damon and Stefan try to turn Elana around.11 Two and a Half Men (7:30 p.m., CBS/Ch. 2): Alan attracts the attention of a married woman.Person of Interest (8 p.m., CBS/Ch. 2): A virus causes the machine to malfunction.Grey's Anatomy (8 p.m., ABC/Ch. 4): Bailey shuts everyone out.The Office (7:30 p.m., NBC/Ch. 5): Jim comes back to Scranton to be with Pam; Andy tries to work up the courage to quit his job and pursue his dreams.Parks and Recreation (8:30 p.m., NBC/Ch. 5): April receives life-changing news. (Season finale)Glee (8 p.m., Fox/Ch. 13): Rachel gets ready for her call-back.Beauty and the Beast (8 p.m., CW/Ch. 30): The mayor is shot.Men at Work (8 and 10 p.m., TBS): Milo decides to break up with Molly.Elementary (9 p.m., CBS/Ch. 2): Sherlock resumes his search for MoriartyScandal (9 p.m., ABC/Ch. 4): The team makes a shocking discovery about the mole.Anger Management (10 and 10:30 p.m., FX): Charlie has one of his patients spy on Kate.