Imagine “Harry Potter” with nothing but Muggles – mean, graceless people without a trace of magic. It would be a dull book indeed.

That, unfortunately, is ” The Casual Vacancy,” J.K. Rowling’s first novel for adults.

The setting is Pagford, a small town in England’s West Country. Barry Fairbrother, a member of the town council, drops dead in a parking lot on his way to dinner with his wife.

Rowling introduces a cross-section of the town’s residents as they learn about Barry’s death. There are shopkeepers and lawyers, doctors and teachers, a social worker and a bunch of teenagers. They’re variously nasty, deluded, selfish, pompous, petty, neurotic and annoying, and they don’t seem to like each other very much.

We also meet a family from the Fields, a public housing estate on the outskirts of town. Terri Weedon is a heroin addict whose 16-year-old daughter, Krystal, can barely string two words together unless one of them has four letters and begins with “F.” The Weedons aren’t much fun to hang out with, but Krystal turns out to be the most sympathetic character in the book.

The town is divided between those who want the Fields to remain part of Pagford and those who want it split off and reattached to the nearby city of Yarvil.

Barry himself was born in the Fields and wanted the impoverished children living there to have the opportunity he did to attend the lovely Pagford primary school, enjoying “the tiny classes, the rolltop desks, the aged stone building and the lush green playing field.”

Several candidates step forward to run for Barry’s seat, with varying motives. Much gossip and back-stabbing ensue.

 I’m trying to make this sound enticing, but it’s hard.

Not that small-town life can’t make fascinating material. Look what Flaubert did with a provincial housewife’s unhappiness in “Madame Bovary.”

“The Casual Vacancy” never lifts off, though. It seems too obvious to say there’s no magic, but Harry Potter aside, every great book needs some alchemy to bring it to life.

You can feel it in “Telegraph Avenue,” Michael Chabon’s new novel about a couple of cranky, sad-sack record-store owners. Chabon’s Oakland has a shimmering reality Pagford never achieves; and while his characters are hardly paragons of virtue, they’re sympathetic in a way Rowling’s never are.

“Harry Potter,” of course, had magic in spades. In addition to reading all the books when they came out, I’ve read the entire series to my son – twice. The world Rowling created was so enthralling and complex that we practically lived inside it, 

I found new delights every time I read the books, and was increasingly awed by Rowling’s careful plotting, the way she subtly laid the groundwork for important revelations early in the series without ever tipping her hand.

Maybe that kind of control works best on a larger canvas; it gives “Vacancy” an airless feeling. Everyone in the book has a secret, and while Rowling carefully portions out information, telling us just enough to keep us reading, we never doubt that by the end all will be revealed in a way that will create maximum embarrassment for everyone.

This isn’t a bad book, just a disappointing one. There’s plenty to admire, starting with Rowling’s obvious pleasure in writing for grown-ups.

Here she is describing Howard Mollison, local deli owner and self-important chairman of the town council:

“He was an extravagantly obese man of 64. A great apron of stomach fell so far down in front of his thighs that most people thought instantly of his penis when they first clapped eyes on him, wondering when he had last seen it, how he washed it, how he managed to perform any of the acts for which a penis is designed.”

There’s plenty of sex, especially among the teenagers. Andrew, a pimply boy with a crush on a beautiful neighbor, Gaia, is ecstatic when she sits in front of him on the school bus:

“Andrew stared, unseeing, at the grimy window, and clutched his schoolbag more closely to him, to conceal the erection brought on by the heavy vibration of the bus.” Take that, Ron Weasley!

It’s interesting to see a billionaire, who was on public assistance when she started the series that made her fortune, writing about class warfare.

There’s a lot to talk about in “The Casual Vacancy” – it tackles big issues that would make it appealing to book groups. I just wish there were more joy in reading it.