February, 1944. A bitter winter grips occupied France, where Marc Reece leads a circuit of British agents risking their lives in order to sabotage the German war effort from within. But Reece has a second mission, secret even from his fellow agents - including Charlotte, the woman with whom he has ill-advisedly fallen in love. He must secure a document identifying a German spy at the heart of British intelligence. The fate of the Allied forces on D-Day is in his hands. But when his circuit is ambushed - with fatal consequences - Reece realizes there may be a traitor in its ranks, putting everything they've been fighting for at risk. Then Charlotte goes missing.