After a harrowing, successful assassination, the two flee to London. They marry, settle in a quiet corner of England during the Blitz, and have a daughter, Anna, born in the middle of an air raid. For a year, it is a miracle. They are a family. Then, the floor falls out from under Max’s life.

In the end, under the grey skies of a secret airfield, the truth is laid bare. Marianne’s past is a tangled web of coercion and survival, but her love for Max and their child is the only thing that was ever true. Faced with an impossible choice between duty and devotion, she makes the ultimate sacrifice to ensure her daughter grows up in a world where the shadows of war can finally fade.

He is called into a cold, windowless room by his superiors. They deliver a soul-crushing ultimatum: they suspect Marianne is a German sleeper agent who adopted the identity of the real Beauséjour after she was killed in France. Max is ordered to conduct a "Blue Dye" test. He is to leave a fake piece of intelligence where she can see it. If she transmits it, he is ordered to execute her with his own hands. If he refuses, he will be hanged for high treason.