Regular Simpsons characters play humorous special roles, occasionally being killed in gruesome ways by zombies, monsters, or even each other. Groundskeeper Willie has died many times in the Treehouse of Horror episodes, mostly by being stuck in the back with an axe, impaled by a sharp object, burned by a furnace and even once by a dolphin. The Halloween episodes also regularly parody many classic horror and science fiction films like "The Shining", "28 Days Later", "A Nightmare on Elm Street", "The Amityville Horror", "The Fly", "Bram Stoker's Dracula", and "I Know What You Did Last Summer". They also parody many Twilight Zone episodes such as "Nightmare at 20,000 Feet", "To Serve Man", "Living Doll", "It's a Good Life", "A Kind of a Stopwatch", "The Little People", and "Little Girl Lost".