Caroline Grant is struggling to accept the end of her marriage when she receives an unexpected bequest. Her beloved great-aunt Lettie leaves her a sketchbook, three keys, and a final whisper...Venice. Caroline’s quest: to scatter Juliet “Lettie” Browning’s ashes in the city she loved and to unlock the mysteries stored away for more than 60 years.

In 1944, British bomber pilot Hugo Langley parachuted from his stricken plane into the verdant fields of German-occupied Tuscany. Badly wounded, he found refuge in a ruined monastery and in the arms of Sofia Bartoli. But the love that kindled between them was shaken by an irreversible betrayal. Nearly 30 years later, Hugo's estranged daughter, Joanna, has returned home to the English countryside to arrange her father's funeral. Among his personal effects is an unopened letter addressed to Sofia. In it is a startling revelation.

As the Great War continues to take its toll, headstrong 21-year-old Emily Bryce is determined to contribute to the war effort. She is convinced by a cheeky and handsome Australian pilot that she can do more, and it is not long before she falls in love with him and accepts his proposal of marriage. When he is sent back to the front, Emily volunteers as a “land girl,” tending to the neglected grounds of a large Devonshire estate. It’s here that Emily discovers the long-forgotten journals of a medicine woman who devoted her life to her herbal garden.

World War II comes to Farleigh Place, the ancestral home of Lord Westerham and his five daughters, when a soldier with a failed parachute falls to his death on the estate. After his uniform and possessions raise suspicions, MI5 operative and family friend Ben Cresswell is covertly tasked with determining if the man is a German spy. The assignment also offers Ben the chance to be near Lord Westerham's middle daughter, Pamela, whom he furtively loves. But Pamela has her own secret.

Londoner Madeleine Grant is studying at the Sorbonne in Paris when she marries charismatic French journalist Giles Martin. As they raise their son, Olivier, they hold on to a tenuous promise for the future. Until the thunder of war sets off alarms in France. Staying behind to join the resistance, Giles sends Madeleine and Olivier to the relative safety of England, where Madeleine secures a job teaching French at a secondary school. Yet nowhere is safe. After a devastating twist of fate resulting in the loss of her son, Madeleine accepts a request from the ministry to aid in the war effort.