The body of eighteen-year-old TV personality Caitlin is found abandoned on a remote beach on the Isle of Lewis. A swimmer and canoeist, it is inconceivable that she could have drowned. Fin Macleod learns that his married son Fionnlagh had been having a clandestine affair with the dead girl and is suspected of her murder, so he and Marsaili return to the island to clear his name. But nothing is as it seems, and the truth of the murder lies in a past that Fin would rather forget.