Adelaide Hills, 1959. At the end of a scorching hot day, in the grounds of a grand country house, a local man makes a terrible discovery. Police are called, and the small town of Tambilla becomes embroiled in one of the most mystifying murder investigations in the history of Australia.

London, 2018. Jess is a journalist in search of a story. Having lived and worked in London for nearly two decades, a phone call summons her back to Sydney, where her beloved grandmother, Nora, has suffered a fall and is seriously ill in hospital.

Seeking comfort in her past, Jess discovers a true crime book at Nora's house chronicling a long-buried police case: the Turner Family Tragedy of 1959. And within its pages she finds a shocking personal connection to this notorious event - a crime that has never truly been solved.