Wallander has become a grandfather and is trying to seize the role as good as it goes, because he wants to be closer to his daughter Linda and her family. When Linda's father in law mysteriously disappears, Wallander is drawn into the case that takes him back in time to the Cold War and the submarine violations in the Stockholm archipelago. At the same time he's starting to suspect that something is not right with him...

A young woman is found dead in Ystad. When the police begin the case, they are told that the woman came from Moldova and that she worked as a prostitute in Sweden. Kurt, who leads the case, decides to seek out the woman's family in Moldova. When he returns to Sweden, he is involved in a car accident and takes a leave of absence from work. Around the same time Kurt finds where is forgetfulness comes from.