Herbert Molin, a retired police officer, lives alone in a remote cottage in northern Sweden. Two things seem to consume him; his passion for the tango, and an obsession with the “demons” he believes to be pursuing him. Early one morning shots shatter Molin’s window... by the time his body is found it is almost unrecognisable. Stefan Lindman is another off-the-job police officer. On extended sick leave due to having cancer of the tongue Lindman hears about the murder of his former colleague and, in a bid to take his mind off his own problems, decides to investigate. As his investigation becomes increasingly complex it is with both horror and disbelief that Lindman uncovers links to a global web of neo-Nazi activity.