Casper opens with a glimpse into the eerie and grand Whipstaff Manor in Friendship, Maine, a vast old house that has fallen into disrepair and rumor. Carrigan Crittenden, a neurotic and spoiled heiress, learns from her late father’s will that she inherits only the dilapidated mansion while much of his wealth has gone to charity. With her loyal lawyer Dibs, she explores ancient papers and finds a map hinting at a hidden treasure in the mansion, setting her on a determined quest to unearth whatever riches lie beneath its creaking floorboards.

The manor is far more than a spooky shell: it’s home to a ghost family. Casper, a friendly ghost of a young boy who died of pneumonia, floats about, eager for connection rather than fear. His three uncles—Stretch, Stinkie, and Fatso—are rowdier spirits more intent on haunting and scaring intruders. They guard the house against unwelcome visitors, mixing ghostly pranks with chaotic noise to keep people away.

Carrigan hires Dr. James Harvey, a paranormal therapist, to rid the mansion of ghosts. Harvey specializes in helping ghosts resolve “unfinished business” so they can move on from the earthly plane. Moving into Whipstaff with him is his teenage daughter Kat, still grieving the loss of her mother and deeply affected by her father’s obsession with contacting the spirit world. Kat is skeptical of the supernatural and weary of her father’s hopes.

Casper, despite being a ghost, is lonely. Watching a news segment about Harvey, he falls for Kat from afar. The friendship he hopes for seems impossible because of the divide between the living and the dead—but Casper tries anyway, using small acts of kindness, solving riddles, and resisting his uncles’ suggestions to scare people. Moments of humor, beauty, and poignancy interweave as Casper’s desire for human connection becomes clear. Meanwhile, Carrigan’s treasure hunt becomes more desperate: she believes the manor conceals not just gold but a formula to grant immortality, and she is willing to go to dangerous lengths to obtain it.

Conflict escalates when Carrigan’s obsession causes outright dangers—betrayal, greed, and greed-driven violence. In the vault she expects riches, but finds only Casper’s baseball, his personal “treasure.” Carrigan becomes a ghost after a tragic accident; her hopes for wealth and immortality unravel. Ghostly pranks turn into moments of tragedy, where themes of death, regret, and the longing to be remembered take center stage. Casper, Kat, and Harvey must confront the mystery of what it means to live, to die, and to move on.

In the end, Casper helps Kat and her father accept loss. Harvey faces danger in his efforts to aid Carrigan’s ghost, but through compassion rather than exorcism, he helps her understand that unfinished business is less about gold or eternal life and more about forgiveness and truth. Kat’s relationship with Casper symbolizes hope: though separated by life and death, bonds of affection, kindness, and memory transcend that divide. The film closes with both laughter and tears, a reminder that sometimes the most powerful things are unseen