One August morning in 1993, the military historian, Richard Holmes, nudged his heels into the flanks of his horse, Thatch, and set off with his four friends to follow the route taken by the British Expeditioary Force nearly 80 years previously, on its retreat from the German offensive at Mons. His ride took him from the Belgian border over the haunting battlefields of the First World War, across the plains and rivers of northern France, to the banks of the Marne, where in September 1914 the BEF played its part in General Joffre's counter-attack against Von Moltke's German armies. Blending an account of his own journey and his strong personal feelings for France with detailed analysis of the 1914 military campaign as well as contemporary testimony, Richard Holmes takes the reader on a journey back through history.