The extraordinary four-month battle on the mountain of Monte Cassino was one of the bloodiest and most controversial of the Second World War. In 1944, Allied troops faced a tough German defensive line there that barred the route to Rome. Hitler's orders were clear: he wanted the line held at all cost, as he thought a successful defence might make the Allies think twice about D-Day. Some of the Allies disagreed about the whole point of the campaign in Italy, were confused and divided, and at times badly mishandled the battle. At the core of the fight was a modern-day siege played out over an ancient castle on the slopes of the mountain. It was a bitter five-day fight that saw the men of both sides suffer terrible losses, but they eventually strove to help each other, in a welcome truce. This remarkable film tells the story of the battle of Cassino through the eyes of the men who fought on both sides. Originally shown as part of Channel 4's Battle for Italy season.