A man is found murdered in his Reykjavik flat, and the police have no obvious leads. The man lived alone and had no family, and of his only two friends, one is serving time for an array of petty crimes and psychotic violence, and the other hasn't been heard of for twenty- five years. Detective Erlendur and his colleague Sigurdur Oli head the investigation team. They find a computer filled with downloaded pornography, the photograph of a young girl's grave and the cryptic note left behind by the killer. Delving into the dead man's past, they discover that forty years ago he was accused, but not convicted, of rape. Now, all these years later, Inspector Erlendur has to follow his instincts when his colleagues lose faith in the investigation. Foraging into the dead man's past, Erlendur discovers that the city of Reykjavik has one or two secrets of its own, secrets it would rather keep.