The Killer Rabbit of Caerbannog is a fictional character in the Monty Python film Monty Python and the Holy Grail. The scene in Holy Grail was written by Graham Chapman and John Cleese. The rabbit is the antagonist in a major set piece battle, and makes a similar appearance in Spamalot, a musical inspired by the movie. The iconic status of this scene was important in establishing the viability of the musical.