When the decapitated heads of an adult male and a young female are discovered in Glasgow, Detectives McBruce and Cartle are mystified. Until YouTube footage of both victims beheaded live on video are brought to their attention. As they investigate, horrific consequences come to light, not only around the two murders in question, but of past events steeped in tragedy and cruelty, and how the abusive happenings over the years in a Childrens Home can lead to a fractured sense of morality. Is all evil bad, may be a question for the fields of religion and psychology. One man though has answered that question himself, and regards the evil he does, not as cruel and murderous, but justice.