Emily Delahunty is an eccentric British romance novelist who lives in Umbria in central Italy. One day while travelling, the train she is on is bombed by terrorists. After she wakes up in a hospital, she invites three of the other survivors of the disaster to stay at her Italian villa for recuperation. Of these are The General, a retired British Army veteran, Werner, a young German man, and Aimee, a young American girl who has now become mute after her parents were both killed in the explosion.

In 1863, Amsterdam Vallon returns to the Five Points of America to seek vengeance against the psychotic gangland kingpin, Bill the Butcher, who murdered his father years earlier. With an eager pickpocket by his side and a whole new army, Vallon fights his way to seek vengeance on the Butcher and restore peace in the area.