Carrigan Crittenden, played by Cathy Moriarty, is the primary antagonist of the movie. She is greedy and only concerned with the inheritance left to her by her late father. She initially threatens to destroy the mansion but eventually discovers a treasure map hidden within the walls. This leads her to hire Dr. James Harvey, played by Bill Pullman, to help her exorcise the ghosts and find the treasure.
Dr. Harvey is a ghost therapist who is grieving the loss of his wife. He moves into the mansion with his daughter Kat, played by a young Christina Ricci. Kat is curious about the ghosts and soon befriends Casper, played by a computer-generated character voiced by Malachi Pearson. Casper is a friendly ghost who longs for a friend and companionship.
However, Casper's uncles, Stretch, Fatso, and Stinkie, played by Joe Nipote, Brad Garrett, and Joe Alaskey respectively, are mischievous and determined to scare off the living and keep the mansion to themselves. They eventually team up with Carrigan to try and get rid of Dr. Harvey and his family.
Throughout the movie, Casper and Kat develop a close friendship, with the latter helping Casper learn how to be a ghost. Meanwhile, Dr. Harvey discovers that Casper's father, who was a famous inventor, had created a machine that could bring ghosts back to life. The machine plays a key role in the movie's climax, with Casper sacrificing his chance at being brought back to life to save Kat.
The movie features a mix of humor, heartwarming moments, and supernatural elements. It was a box office success, grossing over $287 million worldwide and spawning numerous sequels and spin-offs.
