One call could bring ruin to her family name.

Caroline Payne thinks it is just another day at work when she receives a call from Mat Hammond, a doctoral candidate, who has uncovered a dark and scandalous family secret: her British great-aunt defected to the Nazis to marry her German lover.

The letters tell a different story.

In search of answers, Caroline flies to London to search her grandmother’s diaries and her aunt’s letters. In them she discovers the ‘Waite girls’ and a time of peace and luxury in the interwar years that is beyond anything she ever imagined. But the buoyant tone quickly changes as the sisters grow older, fall in love with the same man, and one leaves home to join the glamorous art scene of 1930s Paris - all amid the rumblings of war.

But history won’t let its secrets go so easily.

The more Caroline learns, the more questions she has. Together Caroline and Mat work to dig out answers, uncovering stories of spies and love, of family rifts and of one fateful evening in 1941. Will the truth they uncover heal the decades old family wounds, or will they tear the family even further apart?