One cold autumn night, a woman is found hanging from a beam in her summer cottage by Lake Thingvellir. At first sight it appears to be a straightforward case of suicide, but when Karen, the friend who found her body, approaches Erlendur and gives him the tape of a seance that Maria had attended, his curiosity is aroused. He embarks on an unofficial investigation but at the same time is haunted by the unresolved cases of two young people who went missing thirty years before, and, inevitably, his discoveries raise ghosts from his own past.