In October 1947, tribesmen attacked a convent in the Kashmir valley.
It was the birth of the Kashmir crisis.
Andrew Whitehead, former BBC Delhi correspondent, revisits the scene and tracks down eyewitnesses of the event.
Their gripping testimony reveals how a single incident helped to mould the history of what remains one of the world's most dangerous flashpoints.
He talks to INDIAn and Pakistani politicians about their memories of what happened, local families, children who saw their parents murdered, a 97-year-old nun who survived the attack and even to some of the men behind the invasion itself.
It's a dramatic and compelling story of human tragedy with enormous diplomatic repercussions.