The Big Bang Theory: 10 Best Characters Who Only Appeared In One Episode
9. Dr. Robert Wolcott (Peter MacNicol)
Episode: "The Reclusive Potential" (Season 11, Episode 20)
It only took 11 seasons, but The Big Bang Theory finally managed to give us a character who's weirder than Sheldon. That character is Dr. Robert Wolcott (Peter MacNicol) who is a scientist and Sheldon's pen pal. Sheldon is invited over to Wolcott's cabin in the mountains and he heads there accompanied by Leonard, Howard, and Raj.
It quickly becomes apparent that Wolcott is brilliant and also, to put it in scientific terms, a nutcase. The episode spends a lot of time exploring Wolcott's menagerie of eccentricities, which includes him keeping a jar of his own toenails, serving up squirrel for dinner, and fertilising tomatoes with his own... brand of fertiliser. It's all delightfully entertaining to witness (although, perhaps not while eating dinner). Wolcott's memorability is also aided by MacNicol's superb performance. Not only is he funny, but he also gives a realistic portrayal of a paranoid genius without ever descending into caricature.
While few people would ever want to visit Dr. Wolcott, it is a shame that he never revisited the series and showed us more of his crazy self.