1941. Darkness descends over London as the sirens begin to howl and the bombs rain down. Devastation seeps from every crack of the city. In the midst of all the chaos is a woman gripping a window ledge on the first floor of a Baker Street hotel. She is perched, ready to jump. And as flames rise around her, she is forced to take her chances. 1997. Amy Novak has lost the two great loves in her life: her husband, Michael, and her first love, music. With the first anniversary of Michael's death approaching, Amy buries herself in her job as an archivist. And when a newly declassified file lands on her desk, she is astonished to uncover proof that Agent 'Colette' existed - a name spoken only in whispers; an identity so secret that it has never been verified. Her discovery leads her to MI6 'godmother' Verity Cooper - a woman with secrets of her own - and on to the streets of Paris where she will uncover a story of unimaginable choices, extraordinary courage and a love that will defy even the darkest days of World War Two.