Hoping to save his sick mother, a boy named Gunner and his friend Jo venture into the remote Wild Horse forest to search for a mythical figure who possesses the secret to immortality. When they go missing, Gunner's father Amos must immerse himself in his son's world to find them.

Hoping to save his sick mother, a boy named Gunner and his friend Jo venture into the remote Wild Horse forest to search for a mythical figure who possesses the secret to immortality. When they go missing, Gunner's father Amos must immerse himself in his son's world to find them.