Trivia: Once Bart witnesses Flanders' "murder" the show becomes a takeoff of Alfred Hitchcock's "Rear Window" (1954). Bart is spying on the neighbors while his leg is in a cast, just as Jimmy Stewart does in the film. He even sees an older man with his leg in a cast looking back at him. The man calls for "Grace" to come see the sinister kid. Grace Kelly played Lisa, Stewart's girlfriend in the film. Stewart watches as Lisa goes snooping through the neighbor's house just as Bart watches Lisa Simpson. And when the neighbors come home, they both call for "Lisa" to get out of there.