"Circus of the Scars" is an episode of The Itchy & Scratchy Show.
Itchy and Scratchy are trapeze artists in a circus. They swing towards each other, Scratchy holding onto his bar with his hands, and Itchy hanging upside down by his legs, Itchy pulls out two knives and cuts Scratchy's hands off. Scratchy falls to the safety net, which turns out to be made of extremely sharp wire, as it slices him into diced pieces. An elephant standing next to the net starts eating the pieces of Scratchy as if they were peanuts.
Bart and his girlfriend Greta Wolfcastle watch this episode on a DVD. In the DVD commentary, shown as a picture-in-picture display, Scratchy says that the episode was filmed at 4:00 A.M. and the crew was very cranky. Itchy then suddenly appears in the commentary picture and cuts Scratchy's head off.