It is December 1937 and the Japanese Imperial Army has just entered Nanking. Unable to reach the Safety Zone in Pokou, a group of schoolgirls are hiding out in the compound of the St. Mary Magdalene mission. They are looked after by Father Engelmann, an American priest who has made China his home for many years. The church is supposed to be neutral ground in the war between China and Japan, but eyewitness reports from the outside make it clear the Japanese are not obeying the international rules of engagement. As the soldiers pour through the streets of Nanking, committing unspeakable atrocities on civilians, thirteen Chinese courtesans from a nearby brothel climb over the church compound's walls seeking refuge. Their presence further jeopardizes the children's safety and what happens next will change all of their lives.
