The Ghostly Trio cause panic at a baseball game, and their nephew Casper fails to settle the terrified crowd.

He then creates a pair of spies: Jules and Vincent, and assigns them to bring Wendy to him from where she is living in the country with her three mischievous aunts: Gert, Gabby and Fanny.

Jules and Vincent arrive at Wendy's house to escort the young witch to Desmond, but she narrowly escapes with her aunts.

Casper and Wendy meet in a barn and become friends, but they fear that their guardians will not get along because ghosts and witches are natural enemies.

Wendy feels she has no choice but to cast a high-level spell to cover the Trio in plaster, alerting Desmond of her location.

Casper soon confronts his uncles and tells them that Desmond is coming after the witches and they should help, at which the Trio scoff and refuse.

After finding and confronting the witches, Desmond explains the Oracle's prediction, and after she tries to resist him, summons the Mystic Abyss and casts Wendy into it, with Casper diving inside in an attempt to rescue her.

Before Desmond can turn the witches into fertilizer, a giant three-eyed monster appears and frightens the warlock who trips over Wendy's broom and falls into the Abyss himself.

[3] In the original airing and VHS release of the film, the Casper theme can be heard in the opening sequence performed by Shana Halligan.