Jack the Clown is the leader of the false-military group "The Arny", which attempts to contain the EVIL in Wispydale.
Jack wears clown makeup, allegedly as a ploy to convince outsiders that the group is no threat. In actuality, he is a real clown posing as a commander to fulfill his "destiny" and control the EVIL. He knew that to achieve his goal, he would have to acquire a monopoly on all things that could control the kittens — the Caretakers, which they must kill; the milk, which pacifies them (unbeknownst to him, the kittens know this, and destroyed the milk supply); and the mittens, which they are compelled to recover. The Arny always had control of the mittens, and the Caretakers were captured through magical means as a safeguard to keep the kittens from wreaking havoc across the nation in their attempts to find them. Jack personally wires the town's supply of milk with explosives, leaving the kittens to detonate them and blaming it on Flaky. However, he had not counted on the kittens being able to fly, and is killed as he dangles mittens from his escape helicopter.