The ending of “Marrowbone” is complex and reveals several shocking twists. The story revolves around the Marrowbone siblings – Jack, Billy, Jane, and Sam – who, along with their mother Rose, escape to their mother’s childhood home in Maine to flee from their abusive father. After their mother’s death, the eldest sibling, Jack, promises to keep her death a secret to prevent the siblings from being separated. They bury their mother in the garden and vow to stay together.

However, their seemingly peaceful life is disrupted when they discover that their father, a convicted serial killer, has tracked them down. To protect his siblings, Jack locks them in the attic, but their father manages to enter and kill them. Jack, in a state of shock and grief, bricks up the attic with his father and the bodies of his siblings inside, and starts to imagine that his siblings are still alive. He develops multiple personalities, each representing one of his deceased siblings.

The film’s climax reveals that Jack has been living alone in the house, imagining his siblings’ presence. His girlfriend, Allie, discovers the truth when she finds the diary that explains their tragic past. When she visits the Marrowbone house, she encounters Jack’s alternate personalities and the still-living, though malnourished, father in the attic. In a dramatic confrontation, Jack, with the help of his alternate personality ‘Billy’, kills his father, ending the threat once and for all.

In the end, Allie decides to stay with Jack, who continues to see his siblings as part of his fractured psyche. She chooses not to follow the doctor’s advice to ensure Jack takes his medication, understanding that he is happier believing his siblings are still alive.

“Marrowbone” is a story about love, trauma, and the power of the mind to cope with unbearable realities. It’s a haunting tale that combines elements of horror with psychological drama, revealing the depths of human resilience in the face of unimaginable horrors​​​​.