You cannot keep a good man down. This applies both to the evergreen Ian Rankin and to John Rebus, who refuses to let a minor thing like retirement deter him from chasing down the mad and the bad of the Edinburgh underworld.
Here is Rebus in his 21st outing, slower of step and shorn of his warrant card, but energised by another encounter with his nemesis Big Ger Cafferty and perhaps a last best chance to put the old gangster away.
The opportunity arises when Rebus busies himself with an unofficial investigation into the unsolved death of a young woman in an Edinburgh hotel decades earlier. The cold case file leads him to interview another retired copper, now a night club doorman, who had previously looked into the crime. When his interviewee turns up dead Rebus finds himself embroiled in a tangled web of a case that eventually ensnares Edinburgh financiers, a rock band and crime gangs at both ends of the M8.
Rebus is also ensnared in the continuing ménage-a-trois between himself, Malcolm Fox and his long-suffering sidekick Siobhan Clark. It's the dynamic between these three that has driven recent books in the series, and been responsible for how entertaining they have been. Fox and Clark have a will-they-won't-they thing going on, a source of amusement to Rebus. That relationship has been dealt a severe blow by Fox's reassignment to Police Scotland's major crime squad, a role they both know she is better suited to. Meanwhile Clark's evolution from Rebus' apprentice to her role as 'in loco parentis' (rightly figuring out that if he won't look after himself, someone will have to) continues. And then there is Rebus and Fox, the latter of whom during his time in Complaints, tried to put the former away. Here, Rebus is now back in the teacher role, pushing Fox out of the comfort zone of his by-the-rules straight jacket.
Rankin, as ever, delivers a fascinating plot, but it is the interaction between these three - and to a lesser extent between Rebus and Cafferty - that provides the fizz in a hugely enjoyable and entertaining novel. And happily, the way Rankin leaves the story, there's more to come.