An elderly woman is murdered in a wood by a man she saw setting fire to swans. He buries her corpse with a bible annotating the book of Revelations and from his finger-prints he is identified as Jannek Langas, a religious maniac and arsonist. He has escaped from a secure unit but nonetheless has a healthy bank account in an assumed name. At the same time Anna, a friend of Linda, disappears after a cryptic visit to Wallander. Following Langas's suicide by immolation Wallander learns that Langas and Anna belonged to the same, fundamentalist Christian group and that other members are dying. Wallander must discover who is behind the killings and whether Anna is accomplice or victim - or even alive.