He first appears in Casper: A Spirited Beginning where he runs Ghost Central with his sidekick Snivel who realize that Casper is missing. Kibosh is furious, worried about how he'll look if some rookie ghost is wandering about without any proper schooling. Kibosh orders Snivel to find Casper and bring him back to Ghost Central.
While Casper was being trained by The Ghostly Trio, Snivel called up Kibosh and told him that he's found Casper with the Ghostly Trio and that the trio are teaching Casper unorthodox and illegal ghostly techniques. The trio are planning to use Casper to put Kibosh in his place. Kibosh is outraged.
The Ghostly Trio lose Casper and Kibosh arrives at Deedstown and locks them up in a cage. He then goes to the Applegate Mansion to find Casper. Casper eats a bomb and saves his friend, Chris. Kibosh is impressed with Casper's "scare" and allows Casper to stay with his so-called uncles and leaves them in peace.