Bobby Nusku spends his nights cataloging all traces of the life his mother left behind. By day, he and his best friend Sunny hatch plans to save Bobby from schoolyard torment and his abusive father. Then Bobby encounters a peculiar girl named Rosa and her mother, Val, a lonely divorcee whose job is cleaning a mobile library. When Bobby and Val form a bond that draws unwanted attention, they all abscond in the bookmobile for a picaresque adventure across England.