On a cold January morning, Susan leaves her husband alone for a few minutes and returns to find him gone. He has Alzheimer's disease, and he has wandered alone into a frigid landscape with no sense of home or direction.

The massive search for her husband brings Susan together with Jeff, a search-and-rescue expert and social worker preoccupied with his young wife's betrayal. In Jeff's care is Corey, a young boy rendered mute and abandoned by his family after setting a fire in which his older brother was killed.

As the temperature drops and the search-and-rescue effort builds toward a startling climax, each of the three reflects on their life choices as they struggle with haunting and persistent questions: How am I responsible? What more could I have done?