Shortly after the death of her husband, Amish woman Rachel Lapp takes her son Samuel on a trip to Philadelphia. While in the train station washroom, Samuel sees two men savagely murder a third. Philadelphia detective John Book discovers that people within the police force were involved, and is assigned to escort Rachel and Samuel back home, protecting the boy until the trial. Book blends in with the Amish community, but the corrupt cops Book has exposed are determined to keep their secret, and they come looking for Samuel--to silence him for good.