Bob Newhart will guest-star on an episode of The Big Bang Theory in May, marking the legend's first comedy guest spot since Desperate Housewives in 2005. (And that wasn't really a comedy comedy.) We pictured him as more of a Pawnee resident on Parks and Rec, but okay. According to TVLine, Newhart will play Sheldon's childhood hero Professor Proton, the host of a kid's science show. Your day will come, Bill Nye! Surely someone at TBBT is coming up with a plot for you as we speak.