January 1895. On a freezing morning in the heart of Paris an army officer Georges Picquart witnesses a convicted spy Captain Alfred Dreyfus being publicly humiliated. Picquart is made the French army’s youngest colonel and put in command of ‘the Statistical Section’ - a shadowy intelligence unit. Meanwhile Dreyfus is shipped off to a lifetime of solitary confinement on Devil’s Island - unable to speak to anyone his case seems closed forever. But gradually Picquart comes to believe there is something rotten at the heart of the Statistical Section. When he discovers another spy operating on French soil his superiors are oddly reluctant to pursue it. Despite official warnings Picquart persists and soon the officer and the spy are in the same predicament…