Cujo is a horror novel written by Stephen King, the famous American author. It was first published in 1981. The film adaption of the book was released in 1983.
The story is about a dog (specifically, a St. Bernard) named Cujo, which is owned by the Camber family of Castle Rock, Maine. While chasing a wild rabbit he is bitten by a rabid bat, goes mad within the course of the day and, turns violent as a consequence. The dog begins a killing spree around his family's property.