When an elderly man is found murdered in his basement flat, Inspector Erlendur and his team don't have much to go on, except a photograph of a young girl's grave. They discover that many years ago the man was accused?though not convicted?of horrible crimes. Did his past come back to haunt him? As Erlendur reopens this very cold case, he follows a trail of unusual forensic evidence to the national genetic database, where he encounters the hacker Orn, distraught at the death of his own young daughter. Together, they uncover secrets that are much larger than the murder of one old man?with clues knitted into the bloodline of an entire country.