Tamara Drewe (15)

Whenever a film announces itself as based on a graphic novel, you tend to brace yourself for a whirlwind of bloody violence and death – From Hell, Sin City, Watchmen, Kick-Ass, and the rest. Tamara Drewe, adapted from the graphic novel by Posy Simmonds, is rather different. It does feature scenes of violence: two adolescent girls lob eggs at a passing car (twice). And towards the end even death comes calling, when a character is trampled underfoot by a stampede of frightened cows, and a dog is shot by a hunting rifle. But that's your lot.

The world of Tamara Drewe is more interested in life than death, in particular middle-class rural life as experienced by the sort of people who read The Independent and The Guardian, where this comic saga first appeared in serial form. Do not be deceived by the apparent somnolence of its setting. Beneath the genteel clink of teacups and the cackle of geese bubbles a cauldron of adultery, resentment, longing, jealousy and sexual abandon. "The goat's come into heat" is a sentence that will always have more than one meaning in this milieu. In a pictorially perfect Dorset village, Beth Hardiment (Tamsin Greig) runs a writers' retreat and turns a blind eye to the philandering of her crime-writer husband, Nicholas (Roger Allam). But she finally loses it when his latest infidelity gets found out: "For God's sake, we're surrounded by novelists!" he hisses at her before storming off to London. "Kind of a sleazebag, huh?" suggests Glen (Bill Camp), an American academic struggling with his book on Thomas Hardy. "We call him a prick round here," replies Andy (Luke Evans), gardening hunk and handyman.

The atmosphere has no sooner settled than it's disrupted again by the arrival of Tamara Drewe, incarnated by Gemma Arterton with voluptuous curves, sizzling hotpants and a nose job ("Love the new hooter!"). Once a gawky teenager in the village, she has returned to sell up the home of her late mother, and soon has the menfolk in her thrall. Andy, her former boyfriend, is smitten all over again and volunteers himself as her gardener, but he hasn't much hope once boorish rock-star Ben (Dominic Cooper) razzes up and parks his Porsche in Tamara's drive. His arrival likewise inflames a pair of disaffected schoolgirls whose avid attentions will create mischief for all concerned.

Fans may be inclined to see the adaptation of the book as a piece of cake – organic Victoria sponge, possibly. After all, Posy Simmonds's wonderful drawings provide film-makers with a readymade storyboard, not to mention the minutest details of facial and physical expressiveness. The most important responsibility facing director Stephen Frears was to secure the right cast, and he hasn't failed it. Gemma Arterton has something of a line drawing about her figure already, and brings to the title character an enchanting mixture of shrewdness, ambition and vulnerability – just what you need to write a girl-about-the-countryside column for The Independent (don't remember her at the Christmas party). Roger Allam is less physically like the book's Nicholas, but he inhabits every other irksome part of him to a T. The complacent tone of voice in which he mollifies Beth ("You're a marvel") and the relish he takes in his minor literary celebrity are both eerily right. When he casually condescends to Glen ("How goes the opus?") you wince for the poor academic and his hugely unpromising book. Simmonds's work is piercingly brilliant on writers in general – their love of gossip, their competitiveness, their sensitivity to slights – and the film honours it assiduously, sometimes in direct quotation. Nicholas holding forth before his coven of literary ladies, for instance: "All the girls gathered there like cups round a teapot" (though it's sad to see Cheryl Campbell among them, barely getting a word in edgeways).

The screenwriter Moira Buffini hasn't tinkered much with the book's dialogue, on the sound reasoning that the original could hardly be improved upon. Perhaps I was too impatient to get back to Tamsin Greig's put-upon meekness and Allam's enthralling vileness, but the younger characters, as in the book, seem to me less compelling. Dominic Cooper is suitably uncouth in eyeliner and tight trousers as Ben – "the drummer from Swipe" – though the idiot rock-star has become a stock figure of comedy. His teen idolaters Jody (Jessica Barden) and Casey (Charlotte Christie) are also little pocketfuls of Posy in looks and language; I loved the former's fantasising about a boyfriend with "lush pecs... but also respectful." But I found a little of their boredom and petulance went a long way.

The film is not entirely slavish to the book, however. While it keeps the original's rhythm, splitting into four seasons, it streamlines the narrative and tidies up the ending. Buffini's script deviates slightly, but most profitably, in enlarging the character of Glen and humanising his droopiness. ("I am a real pantyhose," he tells us early on in the novel). Bill Camp, a stage actor in the US and hardly known at all here, invests him with a wistful, almost Chekhovian spirit of longing, which we are made to hope will be rewarded. Thomas Hardy, the presiding influence on the book, is only a spectre here, and mostly by coincidence: Arterton played Tess in a recent TV adaptation. Frears and co are less beady, more indulgent than Posy Simmonds, and that's all right. Tamara Drewe is no less an adaptation for being such an open goal. Even with the safety-net of all those great illustrations it could have missed its mark. Lucky for us it didn't.