The film is about 13-year-old Anton, who—along with his little sister—is sent by his father to the countryside to spend the summer with his grandparents, far away from his friends and everyday life. With his mother in the hospital, his father simply cannot cope with looking after the children. Anton spends his days in an old, overgrown garden filled with apple trees, where he one day meets the beautiful and mysterious girl Ofelia and her dog, Frasse. They quickly become good friends, but as time goes on, Anton realizes that something isn't quite right...