People disappear. Secrets remain . . .

1940: In south-west Ireland, the young and beautiful Lady Charlotte Rathmore is pronounced dead after she mysteriously disappears by the lake of Blackwater Hall. In London, on the brink of the Blitz, Nancy Rathmore is grieving Charlotte's death when a letter arrives containing a secret that she is sworn to keep - one that will change her life for ever.

2019: Disgraced young journalist Ellie Fitzgerald flees Dublin for the safety of rural Kerry. When she discovers a faded letter, tucked inside the pages of an old book from Blackwater Hall, she finds herself drawn in by the mystery of Lady Charlotte's disappearance, and uncovers a long-buried secret...