chunk: Teenager Grace MacLean (Scarlett Johansson) and her best friend Judith (Kate Bosworth) go out early one winter's morning to ride their horses, Pilgrim and Gulliver. As they ride up an icy slope, Gulliver slips and hits Pilgrim. Both horses fall, dragging the girls onto a road and colliding with a truck. Judith and Gulliver are killed, while Grace and Pilgrim are both severely injured. Grace, left with a partially amputated right leg, is bitter and withdrawn after the accident. Meanwhile, Pilgrim is traumatized and uncontrollable to the extent that it is suggested he be put down. Grace's mother, Annie (Kristin Scott Thomas), a strong-minded and workaholic magazine editor, refuses to allow Pilgrim to be put down, sensing that somehow Grace's recovery is linked with Pilgrim's.