1941. Darkness descends over London as the sirens begin to howl and the bombs rain down. Amid all the chaos is a woman gripping a window ledge on the first floor of a Baker Street hotel. And as flames rise around her, she is forced to take her chances. 1997. Alice Tremayne has lost the two great loves in her life: her husband, Michael, and her first love, music. She 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 - an identity so secret that it has never been verified. Her discovery leads her to uncover a story of unimaginable choices, extraordinary courage and a love that will defy even the darkest days of World War Two.