Fictional police detectives don’t usually retire. Morse died in harness, while Reg Wexford and Adam Dalgliesh exist in a fuzzy kind of time that allows them to carry on sleuthing more than 40 years after their debuts in the early 1960s. DI John Rebus, however, has aged realistically over the course of his saga (just like another departing Edinburgh creation, Harry Potter). He begins Exit Music “pushing 60” and 10 days from compulsory retirement. This gives him a deadline both for solving his final case (the murder of Alexander Todorov, a dissident Russian poet attached to the university) and for putting away his archenemy, the gangster Ger Cafferty.

Rebus’s superiors think the killer must have been a mugger. But his investigation with DS Siobhan Clarke points to the possible involvement of Andropov, a Russian oligarch visiting the city and seen discussing deals with a government minister, a leading banker and Cafferty. Todorov may have antagonised Andropov by reciting a bitter political poem in his presence 24 hours before he was killed, and the subsequent death of a sound engineer who taped the reading lends weight to the theory of a less subtle version of the Litvinenko murder.

Rankin responds with aplomb to the challenge of writing a type of story for which there are no direct models – where a sense of an ending is called for, but not the elegiac mood and final statement of values you’d expect when a detective dies. Some of his recent novels have shuttled somewhat mechanically between separate Rebus and Clarke narratives, but here the plotting is enjoyably fluent; and a similar raising of his game is evident in a layering of different themes – from internal police politics to Labour’s battle with the SNP – which is splendidly assured.

His hero has occasionally seemed too limited, closed-in and inflexible a figure, but here his contradictions are made fascinating: a curmudgeon but also an eternal teenager, retaining a student lifestyle of rock and booze off duty; a loner who becomes sociable when coaxing witnesses to talk; someone apparently blinkered but really endlessly curious about people and the daily changes to his city; a remorseless enforcer of the law and yet a habitual breaker of rules and laws.

Using him once again to link Edinburgh’s underworld with the “overworld” of its interlocking elite, Rankin adroitly produces a denouement that wraps up the who-dunnit perfectly but also plays literary games. There are nods to Dostoevsky’s Crime and Punishment, James Hogg’s Confessions of a Justified Sinner, perhaps to Sherlock Holmes’s exit in His Final Bow. The last scene, bringing together Rebus and Cafferty, is a sly, ingenious reworking of Holmes’s apparently fatal tussle with Moriarty at the Reichenbach Falls – another Scottish author attempting to retire his detective but failing, you can’t help but notice. The possibility of Rebus returning is conspicuously left open.

Exit Music by Ian Rankin
Orion £18.99 pp380
Buy the book here at the offer price of £17.09 (inc p&p)

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