When thirteen-year-old Mark Miller runs away from his home in north central Washington, he does it right: he carefully plans the details of his escape, packs exactly what he needs, and sends the police and his parents chasing him in the wrong direction. Back home, his best friend Jessie wrestles with the news of his disappearance. She finds out the cancer Mark has fought for years has returned, and this time there may be nothing the doctors can do.