1936. After a scandalous celebrity divorce, British tennis star Nevile Strange and his ex-wife, Audrey, make the unthinkable decision to spend the summer together at Gull's Point, the coastal estate of his aunt, Lady Tressilian, and their childhood home.

When a body is found on the beach below Stark Head, an extraordinary story unfolds. Meanwhile, at Gull's Point, tensions simmer. In a bid to blow off steam, the Gull's Point crowd takes a trip to the pleasure hotel across Easterhead Bay.

A shocking line is crossed and Kay, seething, swears off her husband for good. An unbearable tension permeates the house as the guests take to their beds for a restless night.

Leach must return to the house and face a painful truth. Furious at the audacity of the murder, and the toll it takes on Sylvia, Leach vows to catch the killer, and as the evidence begins to come in thick and fast, he finds his copper's heart beating again.