“This animated character’s claim to fame is the violent death he suffered at the end of every episode.”

If we were playing Comedy Jeopardy!, the obvious answer would be, “Who is Kenny from South Park?” But there’s another response the judges would have to accept — Mr. Bill, the Play-Doh putz who was regularly dismembered during the early days of Saturday Night Live.

Just as the initial South Park cartoons were a DIY comedy adventure, Mr. Bill grew out of a fertile mind with zero budget. It all started when Dan Aykroyd announced a home movie contest during SNL’s first season, inviting viewers to create their own comedy shorts for possible inclusion on a future episode. Showing the home movie on national television was considered the prize — no other reward was offered.

Enter Walter Williams, an accounting school dropout from New Orleans. He thought it would be funny...