Boulogne - May 23 1940. A town under siege. A rampant German panzer division hammers at its gates. Panic in the street and chaos on the docks. Air Raids. Frightened refugees and dispirited Allied soliers scramble to escape. Churchill sends the Guards: the Irish and the Welsh, to help the French garrison stem the German tide. Two fine battalions with no support against an armoured division. A hopeless task. Hours later he pulls them out but some are left. The final act-riffles against tanks across the Bassin Napoleon. The last bullet. The bitter taste of surrender.