In 2002 in Vilnius, Lithuania, scientists were stunned to discover the remains of some two to three thousand French soldiers, the first mass grave of its kind ever uncovered. How they died opens a window on one of the greatest military disasters in history. Having fought their way across Europe, Napoleon's armies, freezing cold, malnourished and exhausted, were stalled outside Lithuania's capital city. Thousands of those who reached Vilnius either died outside the city gates or inside of shock, gangrene, typhus, dysentery, or starvation. No one really knows for certain how the French soldiers died the way they did, the victims names were unrecorded and their deaths were unmarked. This insightful documentary aims to shed new light on this long standing military mystery and attempts to explain what happened to Napoleon's lost army.