Each summer a group of families holiday together in St. Ives, Cornwall, but in 1972 their lives are shattered and they never meet up again. In a lane in the village of Zennor a hotel porter is found fatally poisoned. Later that week the body of another man is washed ashore. Grant Morrison, then aged seventeen, has long been troubled by the two deaths and their aftermath and, decades later, decides that the time has come to uncover the truth.