As much as the American participation in World War II has been clearly noted, the presence of the American soldiers - nicknamed the 'Sammies' (sent by Uncle Sam) - on French soil during the Great War is virtually unknown. And yet, 2 million Sammies arrived in France between 1917 and 1918 to fight alongside French and English troops. They have been stuck in the trenches, buried in a rain of shells, exhausted by the noise and tormented by hunger. 53,000 perished, 234,000 were injured and 4,500 went missing. Without the participation of these men, the conflict could have ended entirely differently. Indeed, they proved to be the undisputed artisans of Allied victory and hoisted their country to the rank of world's leading military and economic power. Through unreleased archives and contemporary footage shot in the archeological digs of World War I's battlefields, this film tells the heroic and tragic tale of the American soldiers in this terrible conflict. Still today, many clues, objects and graves are randomly uncovered during the course of archeological projects carried out around the front lines and in the battlefields. They provide an emotional account of this violent tale and of the emergence of a nation.