In an old and charming mansion on the edge of a swamp, a young therapist named Kat and her father, a parapsychologist, move in search of a new life. However, upon arrival, they soon discover that the house is inhabited not by ordinary tenants, but by a group of mischievous ghosts and a peculiar little ghost boy named Casper. Unlike his fellow spirits, who are somewhat more playful—if you could call it that—Casper is a friendly spirit who longs for companionship and friendship, as he feels lonely and trapped in a world that fears him.
As Kat tries to adapt to her new life, a special bond forms between her and Casper. Together, they explore the house and share moments ranging from fun to heartfelt. However, the arrival of two ghost hunters in search of a treasure that will unleash true chaos in the house changes the dynamic. Kat and Casper's friendship is put to the test, and she must decide whether to help her new friend or protect her father from the dangers lurking in their home. As everything spirals into a whirlwind of laughter, scares, and lessons about friendship and acceptance, an emotional story unfolds about life, death, and what it truly means to be a good friend.