Detective Inspector Siobhan Clarke is investigating the death of a senior lawyer during a robbery. But the case becomes more complex when a note is discovered, indicating that this may have been no random attack. When local gangster Big Ger Cafferty receives an identical message, Clarke decides that the recently retired John Rebus may be able to help. He's the only man Cafferty will open up to, and together the two old adversaries might just stand a chance of saving Cafferty's skin. But a notorious Glasgow crime family has arrived in Edinburgh, too, tailed by a team of undercover detectives. There's something they want, and they'll stop at nothing to get it. DI Malcolm Fox's job is to provide the undercover squad with local expertise, but he's soon drawn in too deep as the two cases look like colliding. Meanwhile, an anonymous killer stalks the nighttime streets, focussed on revenge. It's a game of dog eat dog in the city as in the wild.