An idyllic island holds a dark secret . . . - On a hot August day in 1994, 76 holidaymakers travel to an island off the North Norfolk coast. Only 75 return alive – a young man is murdered, the case left unsolved. Twenty years later, using state-of-the-art forensics, the DNA results of a bloodsoaked towel prompts DI Peter Shaw to summon all 75 original suspects to a mass screening, but one of them, the beautiful Marianne Osbourne, is found dead in her bed. Is there a link to the 1994 murder? DI Shaw and DS Valentine become immersed in the dark secrets of an isolated community.