Cujo is a friendly St. Bernard dog, who was the pet of Brett, the son of a mechanic who liked to abuse the dog, who lived on a farm. While chasing a rabbit down a rabbit hole, Cujo gets bitten by a rabit bat. Cujo starts to succumb to the disease, reacting quickly to loud noises, and introducing violent behaviour. He mauls Brett's dad, and the neighbour, to death. He nearly turns on Brett, but can't bring himself to and runs away. Soon, housewife Donna and her son Tad drive to the farm, but are attacked by Cujo. They are safe in their car, but the alternator dies, which leaves them stranded, with the vicious dog waiting outside, all while Donna's husband is on a business trip. The sheriff arrives and finds the bodies of Brett's dad and the neighbour, but is killed by Cujo. Donna tries to get out of the car, but Cujo stops her and bites her in the leg whilst she tries to get back into the car. Cujo bites off the car handles. Donna takes a baseball bat and fights Cujo, battering him with the bat until it breaks. Cujo lunges at her, but is impaled on the jagged handle. Donna takes Tad, who has dehydrated due to the heat, and runs to the house, but Cujo revives and makes one last attempt at killing them. Donnna takes the sheriff's pistol and shoots Cujo in the head, killing him
- Gary Pervier: Neck Bitten Out
- Joe Cambers: Face Eaten
- Sheriff George Bannerman: Knocked off of catwalk and mauled.
- Tad Trenton: Sunstroke from being trapped in car.