Casper Meets Wendy is a 1998 direct-to-video family fantasy-comedy film based on the Harvey Comics cartoon characters Casper the Friendly Ghost and Wendy the Good Little Witch. The film is a sequel to Casper: A Spirited Beginning, and is the second spin-off/prequel of Casper. Saban Entertainment, co-produced the project. The film also marks the second Casper film to co-star Cathy Moriarty, who played the villainess in the 1995 film.
This was the first major film for Hilary Duff, who was 10 years old when the film was released on September 22, 1998, six days before her 11th birthday, and was met with mostly negative reviews from critics, but was considered an improvement to its predecessor. It then aired on October 27, 1998, four days before Halloween, on Fox Family.
A mysterious "spaceship" floats over a baseball game eventually revealing Stretch, Stinkie, and Fatso, The Ghostly Trio (Voices by Jim Ward, Bill Farmer, and Jess Harnell), who cause panic in the ballpark. Their nephew Casper, attempts to settle the terrified crowd, but they are just as scared of him as they are of his uncles. The park empties, and after watching their effect with satisfaction, Casper's uncles plan a vacation.
Meanwhile, a malevolent warlock named Desmond Spellman (George Hamilton) believes himself to be the greatest warlock to have existed until he receives an unwelcome message from the Oracle in the Mirror, who tells him that in the future, none other than Wendy the Good Little Witch (Hilary Duff) will surpass him in being the greatest witch ever. To avoid this, Desmond plans to get rid of her once and for all with the advised "Mystic Abyss", a dimensional rift that can destroy living beings upon entering. He then creates a pair of spies: Jules and Vincent (Richard Moll and Vincent Schiavelli), and assigns them to bring Wendy to him where she is living in the country with her three mischievous aunts: Gert, Gabby, and Fanny (Cathy Moriarty, Shelley Duvall and Teri Garr).
Jules and Vincent arrive at Wendy's house to escort the young witch to Desmond, but she narrowly escapes with her aunts. To keep Wendy safe from Desmond, her aunts hide and vacation at a resort hotel which happens to be the same place in which Casper and his uncles are vacationing.
Casper and Wendy meet in a barn and, due to their amiable personalities and having been bossed around by their respective guardians, they become great friends. Unfortunately, they fear that each of their elderlies will not get along because ghosts and witches are natural enemies. However, the pair are certain their guardians would get along if they only got to know each other. In order to do that, they devise a plan. Casper tricks the Ghostly Trio to break the record for possession so that he can learn how to do it, and they possess three men at the party. Wendy convinces her aunts to go to the party to meet men. Thanks to their plotting, they meet and soon the Trio are flirting with the three witches, who are posing as regular women.
Though everything goes well at first, with the ghosts and witches unwittingly enjoying each other's company and finding that they have a lot in common, the plan is spoiled when the possession wears off and the ghosts' real selves are revealed to Wendy's aunts, who, in turn, reveal their real selves and threaten them with magic. However, as Wendy explains to Casper, she and her aunts cannot use any high-level magic or else Desmond will be able to track them down. She begs Casper not to tell anyone about this. Unfortunately, when the Ghostly Trio suspects that Casper is protecting the witches, they interrogate and pressure him into blurting out that the witches cannot use their powers, prompting the Trio to terrorize Wendy and her aunts. Wendy feels she has no choice but to cast a high-level spell to cover the Trio in plaster, thus alerting Desmond's magic tracker of her location.
Distraught that Casper broke his promise, Wendy ends their friendship. Casper soon confronts his uncles and tells them that Desmond is coming after the witches and they should help. The Trio scoff at first and refuse, but Casper reminded them that at the party the Trio showed that they could get along with the witches if they put their differences aside.
Before the witches can evacuate the resort, Desmond and his spies arrive. 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 to destroy her, with Casper diving inside in an attempt to rescue her. Wendy's aunts attempt to battle Desmond but are no match for him. Before Desmond can turn the witches into fertilizer, a giant three-eyed monster appears and frightens the warlock who, while recoiling in fear, trips over Wendy's broom and falls into the Abyss himself. The monster turns out to be the Ghostly Trio, who have a change of heart and decide to help after they combine their powers to defeat Desmond. While they hold the door to the Abyss open, Wendy's aunts pull her and Casper out.
Both Casper and Wendy are weak and unconscious from being inside the Abyss; but with encouragement and comfort from their guardians, Casper is restored by his uncles, and Wendy is treated by her aunts. After a touching reunion between the witches and an awkward one between the ghosts, the witches thank the Trio for helping them. The Oracle then proclaims that Wendy is the greatest witch because she did something no other witch ever could; she befriended a ghost. Later, Casper, his uncles, Wendy, and her aunts, all bid each other goodbye. Before flying back home with her aunts, Wendy gives Casper a goodbye kiss, causing him to blush.