Question: Waylon Smithers, often referred to as Mr. Smithers, debuted in the January 21, 1990 episode of The Simpsons as the personal assistant to which Springfield Nuclear Power Plant owner?
Sentence (from "Waylon Smithers"): Waylon J. Smithers Jr., usually referred to as Mr. Smithers or simply Smithers, is a recurring fictional character in the American animated sitcom "The Simpsons", who is voiced by Harry Shearer.
Relevant evidence: Yes