Examines the critical battle fought between the French and the Germans in 1914, the first great battle of World War I.

August 1914 : Sabbath at Mons -- Old rivalries and new alliances : the origins of World War I -- The opposing forces : the men and means for making war -- The opening battles : Liege, Namur, and the frontiers of France -- The great retreat : Germans at the gate -- Decision at Chatillon : the battle begins -- Moments of glory : deciding the fate of France -- Turning point : the battle ends -- After the battle : the might-have-beens of the Marne.