Glasgow 1975. A deadly fire. An arson attack on a Glasgow warehouse causes the deaths of a young mother and child. Police suspect it's the latest act in a brutal gang warfare that's tearing the city apart - one that DI Duncan McCormack has been tasked with stopping. A brutal murder. Five years ago he was walking on water as the cop who tracked down a notorious serial killer. But he made powerful enemies and when a mutilated body is found in a Tradeston slum, McCormack is assigned a case that no one wants. The dead man is wearing a masonic ring, though, and Duncan realizes the victim is not the down-and-out his boss had first assumed...