Detective Inspector Lorimer's worst nightmare is a serial killer loose in his city. But two serial killers operating at once in Glasgow is a nightmare come to life. Is there any link between the brutal slaying of prostitutes in the backstreets of the city and the methodical killing of several unconnected businessmen? Lorimer is never one to jump to conclusions but something about these cases just doesn't add up.

When the latest murder is that of a prominent politician, Lorimer finds the media's relentless scrutiny turned on his investigation. Psychologist Solly Brightman is helping with both cases, but someone within Lormer's team is unwittingly sabotaging their efforts by leaking confidential police information. Their whispers will cost lives...

As the freezing winter weather grips Glasgow, two killers are relentlessly taking lives in cold blood. For Lorimer, time is running out.