Stephen Booth "The Devil's Edge"

Having sorted out some of the Diane Fry issues in Lost River, Stephen Booth has taken the soap opera side of things several steps further in The Devil's Edge but it's always the crime side of things that provides the series with an ongoing raison d'être.

With an apparently well-off couple the victims of a bashing in the course of a home invasion the investigation gives newly promoted Ben Cooper and his squad something to get their teeth into while Diane Fry has been moved sideways into a management-training scheme where boredom and the unwelcome attention of a male colleague brings things unstuck and creates a need to give her something useful to do.

That something comes in the form of an incident involving Cooper's brother, who shoots midnight trespassers. It's a case where conflict of interest rules Cooper out of the investigation, though he's inclined to offer helpful suggestions, regardless of what the regulations might say.

The fact that Cooper's suggestions help to rule out a possible move to Derby is a nice touch as well. Brought in to supervise the Matt Cooper investigation, and with the matter resolved, DCI Mackenzie was preparing to leave when he drops the following bombshell.

You're a real farm girl, aren't you? A proper expert on rural life. I was thinking of offering you a job with my team in Derby, but you're obviously more at home here in the country.

In the rest of the soap opera scenario Ben Cooper and SOCO Liz have announced their engagement, and at the end of the story Diane Fry and the recently recruited war widow and RAF Police veteran Carol Villiers, an old school acquaintance of Cooper's, hitting it off well.

And, with Diane Fry removed from a supervisory capacity, Gavin Murfin, nearing the point where he can collect his superannuation emerges as a wryly sardonic character with an ability to do something other than munch his way through everything in sight.

But it's the latest incidents in what seems to be a series of home invasions that delivers the main plot line here, and it's a particularly strong one this time around. As far as the media are concerned, the events in the middle class rural village of Riddings are the latest burglaries  by a gang they've nicknamed The Savages but Cooper's not so sure.

For a start, unlike other cases in the same suspected series of offences, when Zoe and Jake Barron are bashed the only things that have disappeared are a mobile phone and a wallet. It's not as if their home, set on the edge of an affluent conclave that's hardly your common or garden rural village, lacks objects you'd expect to attract the would-be burglar's attention.

And as Cooper and company set about the investigation it's obvious that Riddings isn't a haven of bucolic tranquility. Nestled at the foot of an imposing ridge of solid rock, Riddings is a community of fenced-off, gated properties where security cameras are the rule rather than the exception, and the inhabitants aren't inclined to socialise outside the annual village show. There's no pub, post office or sense of community and and the villagers almost invariably have personal issues.

There's the village snooper, who discovers Zoe Barron's body and alerts the authorities, a greedy and territorial lottery winner, a disgraced headmaster on leave after an incident with a student and any number of others with a possible motive, the capacity, and in most cases the likely opportunity to do away with a neighbour though there are few obvious leads among an abundance of suspects.

Under a veneer of respectable affluence there's a seething mass of resentment and conflict as a second home is broken into with a victim apparently dead of fright and with the pressure on the investigation is increasingly based around Cooper's instincts as he solves the puzzle. You're left pretty much in the dark until the final rush at the end of the story, which is the way things should run in crime fiction, and Booth has managed this variation on the genre deftly, weaving the main plot line around the side issues and driving things forward right to the very end.

One of the best in the eleven book series, and one that has me looking forward to the sequel.