Bart Simpson (voice of Nancy Cartwright) is riding his skateboard home after a hard day at school when he falls down a flight of stairs and finds himself in "The Legitimate Businessman's Social Club," a meeting place for Fat Tony (voice of Joe Mantegna) and other kingpins of the Springfield Mafia. Forced to mix a Manhattan, Bart proves to be a pretty good bartender, and Fat Tony offers him a job after school. But Bart's duties at the Social Club take up more and more of his time, and when Principal Skinner (voice of Harry Shearer) makes Bart stay after school, Fat Tony is not amused. The next day, Skinner disappears and is soon presumed dead, and when Police Chief Wiggum (voice of Hank Azaria) confronts Fat Tony, he pins the blame on Bart. Soon Bart is on trial for murder, and the various members of the "Social Club" testify that the boy is actually the godfather of a vast criminal empire. "Bart The Murderer," which first aired on October 10, 1991, also features a voice performance from Neil Patrick Harris, who plays "Bart Simpson" in a made-for-TV movie, Blood On The Blackboard: The Bart Simpson Story.
by Mark Deming synopsis