Inspector Rebus, Ian Rankin's 50-ish, going-to-seed tough guy, is in trouble as usual, but this time it's on the first page of this 15th installment in the series.

		A Question of Blood By Ian Rankin Little, Brown $22.95

He's lying in an Edinburgh hospital with his hands burned and bandaged, and with questions to answer about a small-time crook who died in a house fire the same night he and Rebus were seen together.

His partner, Detective Sergeant Siobhan Clarke, is filling him in about an apparently random shooting in a private school, where an ex-soldier has killed two and wounded another before turning the pistol on himself. One of the victims turns out to be the son of a cousin whom Rebus hasn't seen in 30 years.

Thus begins one of Rankin's most intricate, suspenseful and plausible plots, in which Rebus, at loggerheads with his boss and the Scottish equivalent of Internal Affairs, ends up solving three cases that only appear unrelated.

As always with Rankin, well-drawn characters, from a Goth schoolgirl to shadowy British army spies to a dandified dealer in illegal arms known as Peacock Johnson, flesh out the story.

But no one is more compelling than the flawed but somehow likable Rebus. His wife is estranged, his daughter rarely calls, and he has few friends. (DS Clarke, who has her own problems, is a notable exception.)

He drinks evenings away with shots of single malt at a neighborhood pub, then falls asleep on the chair in his flat to the blasting of vintage Scottish and English rock (remember Rory Gallagher?).

His dreams are troubled by past mistakes; the shadow of time looms over Rebus and many of the other characters in Rankin's novels.

On the job, Rebus admits that he's a "bull in a china shop." He hates crooks so much that he is prone to leap at them before he looks, harming himself and others. But he is also intuitive, just about fearless and 101 percent relentless -- a hound from hell if you're unlucky enough to be the bad guy he's up against.

He's also apt to commit small acts of kindness that he knows will never redeem him.

The city of Edinburgh, where the author lives, also gets star billing in the Rebus books. Painted with quick, telling strokes, the workaday, seedier side of Scotland's capital springs up around the reader, who is transported to greasy chip shops and grim high-rise projects.

But of all Rankin's assets, it's his dialogue that impresses most. It kicks the story forward, not unlike the rhythm section of Rebus' beloved Stones. The speakers feel like sentient beings -- they shade, allude and obfuscate, and they are conscious that the person they're talking to is doing the same.

Clues emerge from offhand remarks or from what is left unsaid, and after a while the reader is hooked into measuring each word as carefully as does Rankin's hero.

What's more, Rebus has a wit sharper than a Highlander's sword. His comebacks and putdowns are delicious. When he gets angry at a crook who is almost his verbal equal, you may want to read with oven mitts.

In some ways, Rankin's noir-ish hero is not much different from a slew of other disaffected detectives past and present -- good but hard-shelled men with lousy personal lives who usually go it alone in a world where corruption reaches from the bottom of society to the top.

Rankin just does it better than most, which has made him immensely popular in the U.K. and not unknown to American mystery devotees. At his best, in novels such as "Black and Blue," "Set in Darkness" and "Dead Souls," his writing will interfere with your work and your love life. No question, "A Question of Blood" belongs on that list.