That decorous but emphatic thumping sound you hear, from somewhere far overseas? It's Oscar Wilde, rolling in his grave.

"A Good Woman," a ham-fisted adaptation of Wilde's play "Lady Windermere's Fan," suffers from a staggeringly bad miscasting of its central role and from a cut-and-paste screenplay that substitutes random insertions of Wilde epigrams for character. Screenwriter Howard Himelstein has turned the story upside down and moved the action from 1890s London to 1930s Italy for no particular reason except, perhaps, the thrill of showing the Amalfi Coast (which, it must be said, plays its role impeccably). A few characters are made American, presumably so American movie stars won't have to go to all that bother of learning a British accent. And the result is a prettily costumed mess.

Helen Hunt plays Mrs. Erlynn, a woman of ill repute who appears to be having an affair with Robert Windermere (Mark Umbers), a rich and newly married young man. His naive wife, Meg (Scarlett Johansson), just turned 21, is horrified to hear of the gossip and plots her own revenge, but events take a surprising turn. Well, it would be surprising, except that director Mike Barker bungles a key moment of revelation; it's tossed away so cavalierly that you just might miss it.

Hunt, who can be natural and affecting in contemporary roles (in particular "As Good As It Gets"), is completely at sea here, flatly intoning her lines as if she'd memorized them phonetically. Mrs. Erlynn needs to have an air of slightly insouciant mystery; as Hunt plays her, she's like an earnest speech therapist in '30s shoulder pads. It's a mystifyingly bad performance, and it drags down the entire movie; you can't imagine why the entire community is fascinated by this woman.

Johansson, whose soft vulnerability well suits this role (though the sausage curls on her head aren't doing her any favors), has some good moments, as does the ever-reliable Tom Wilkinson, who manages to make us believe that his agreeable nobleman has fallen in love with Mrs. Erlynn. And the costumes and sets are lovely to look at, particularly the Windermeres' spectacular Amalfi villa.

But there's nothing at the core of this Wilde-made-mild; the biting wit of the original is replaced by what feel like drive-by witticisms. A few of the playwright's trademark gems sparkle through, while others have been shamefully tampered with. Consider this example: Wilde's "Crying is the refuge of plain women and the ruin of pretty ones" has been changed to "Crying is the refuge of plain women. Pretty women go shopping." Perhaps the makers of "A Good Woman" need to do a little shopping, to see if they can replace that tin ear.

Moira Macdonald: 206-464-2725 or mmacdonald@seattletimes.com