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.

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.

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.

Thirteen-year-old Lisa has escaped from Nazi Germany on the Kindertransport. She arrives in London unable to speak a word of English, her few belongings crammed into a small suitcase. Among them is one precious photograph of the family she has left behind. Lonely and homesick, she is adopted by a childless couple. But when the Blitz blows her new home apart, she wakes up in a hospital with no memory of who she is or where she came from. The authorities give her a new name and dispatch her to a children's home. With the war raging around her, what will become of Lisa now?

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.