John Rebus, the Edinburgh police officer appearing in a novel by Ian Rankin for the 24th time, is growing old, but his mental acuity and sleuthing skills are as keen as ever. Retired from the force because of Chronic Obstructive Pulmonary Disease, he can no longer climb the stairs of his spacious apartment in a walk-up "tenement," and is being helped by his former colleague Siobhan Clarke to move into a smaller flat on the ground floor.

Downsizing is hard for all of us — including Rebus' small but feisty dog Brillo — and for the aging detective, his old case files are among the most difficult possessions to part with.

There are a lot of metaphors here. The titular dark times include old age, but also past misfortunes and mistakes. Rebus' ancient Saab, which breaks down at the most inconvenient times, reflects its owner's aging body. Both Rebus and the Saab manage to make it through the novel, but only barely. The plot is filled with contrasts: old vs. young, a child's reaction vs. an adult's to tragedy and loss, urban vs. rural, southern Scotland vs. the North, light vs. dark, and perhaps most painfully, the mind vs. the body.

"A Song for the Dark Times" is actually two parallel stories, although the author eventually brings them together. During his move, Rebus gets a call from his daughter Samantha, who has relocated to a fictional town called Naver in the real highland county Sutherland. Samantha has distanced herself from her father — emotionally and physically — because of his having put police matters above family during her formative years. But now, Samantha's husband, Keith, has disappeared. She and their daughter are alone and desperate, so Rebus takes his dilapidated jalopy up north, leaving Siobhan to care for his apartment and the dog.

When Rebus arrives, he receives a cool reception from his daughter, who remains ambiguous about their relationship. When Keith turns up murdered, Rebus meets an even colder treatment from the local detective, Robin Creasy, who not only resents unrequested assistance from the old city cop, but considers Samantha to be the prime suspect. A weakness of the narrative is that Rankin too often allows the uneasy rapport between father and daughter to take focus from the crime element. But it does fill out gaps in what fans already know about the indomitable Inspector.

The second murder is Siobhan's case, back in Edinburgh. Salman bin Mahmoud, a wealthy Saudi student (and playboy) who is also a fanatic James Bond fan, is found in a seedy part of the city. There are international implications, including but not limited to Brexit, and a Detective Inspector Malcolm Fox is brought in from Manor Crimes Division to be Clarke's partner in the investigation. It's an uneasy affiliation, with each inevitably infringing on the other's territory.

The seemingly unrelated crimes are brought together by a beautiful though unpleasant young heiress named Isabella Meiklejohn — a close friend of the Saudi student and daughter of a shady businessman who owns much of the land in Sutherland County. Coincidence and complications pile up. With this tale unfolding in Rankin's fluid and colorful prose, we can hope that Rebus and his old Saab, having survived one more adventure, will return next year for another bout of Caledonian chicanery.

Robert Croan is an editor at the Pittsburgh Post-Gazette.

A Song for the Dark Times
By: Ian Rankin.
Publisher: Little, Brown, 336 pages, $27.