For Sideshow Bob's father, see Robert Terwilliger, Sr.. For other uses, see Sideshow Bob (disambiguation). "Hello, Bart." ―Sideshow Bob, upon greeting Bart Simpson. "No! That's German... for 'The Bart, The.'" ―Terwilliger, testifying in court Dr. Robert Onderdonk "Bob" Terwilliger, Jr., more commonly recognized by his stage name, Sideshow Bob, is a recurring antagonist in The Simpsons. He was originally Krusty the Clown's sidekick, before starting a life of crime that began with an attempt…