Summer 1924. On the eve of a glittering Society party, by the lake of a grand English country house, a young poet takes his life. The only witnesses, sisters Hannah and Emmeline Hartford, will never speak to each other again. Winter 1999. Grace Bradley, 98, one-time housemaid of Riverton Manor, is visited by a young director making a film about the poet’s suicide. Ghosts awaken and memories, long consigned to the dark reaches of Grace’s mind, begin to sneak back through the cracks. A shocking secret threatens to emerge – something history has forgotten but Grace never could.

Thirty-eight year old Cassandra is lost, alone, and grieving. Her much loved grandmother, Nell, has just died and Cassandra, her life already shaken by a tragic accident 10 years ago, feels like she has lost everything known and dear to her.

England, 1959: Laurel Nicolson is 16 years old, dreaming alone in her childhood tree house during a family celebration at their home, Green Acres Farm. She spies a stranger coming up the long road to the farm and then observes her mother, Dorothy, speaking to him. And then she witnesses a crime.

1961. On a sweltering summer’s day, while her family picnics by the stream on their Suffolk farm, 16-year-old Laurel hides out in her childhood tree house, dreaming of the bright future she can’t wait to seize. But before the idyllic afternoon is over, Laurel will have witnessed a shocking crime that changes everything. 2011. Now a much-loved actress, Laurel finds herself overwhelmed by shades of the past. Haunted by memories and the mystery of what she saw that day, she returns to her family home and begins to piece together a tale of three strangers from vastly different worlds.

A lost child: On the eve of the first world war, a little girl is found abandoned on a ship to Australia. A mysterious woman called the Authoress had promised to look after her – but the Authoress has disappeared without a trace. A terrible secret: On the night of her 21st birthday, Nell O'Connor learns a secret that will change her life forever. Decades later, she embarks upon a search for the truth that leads her to the windswept Cornish coast and the strange and beautiful Blackhurst Manor, once owned by the aristocratic Mountrachet family.