Nigel Cole’s debut feature is a pleasant little comedy with the soul of one of those old, much-loved Ealing pictures of the forties and fifties, but it’s overlayed with a coating of Hollywood glitz that seems ill-suited to its mood. The result is a hybrid that’s amusing enough, but in the last analysis comes across as neither fish nor fowl.

Like such classics as “Passport to Pimlico” and “Whisky Galore” (both from 1949–the latter was rechristened “Tight Little Island” for U.S. release) or “The Titfield Thunderbolt” (1953), “Saving Grace” is set in a very insular English community populated by harmless eccentrics who, under the leadership of one particularly driven inhabitant, conspire in some (usually illegal) activity for a good cause. In this case the locale is a village in coastal Cornwall, where much-loved local matron Grace Trevethan (Brenda Blethyn) finds herself broke and soon-to-be-evicted after the death, by suicide or accident (he fell out of a plane), of her apparently prosperous husband, who had squandered his money, mortgaged the homestead, and left behind a London mistress to boot. Grace’s dire circumstances compel her, as an avid gardener, to concoct a plot with her marijuana-smoking groundsman Matthew (Craig Ferguson) to convert the estate’s greenhouse into a hemp-growing factory; the notion is to sell off one crop, which will enable Grace to save her house and Matthew to earn enough to wed his long-time girlfriend, who just happens to have gotten pregnant. The scheme entails lots of complications, of course, so that we watch dotty Grace trying to make contact with drug dealers in London to get a good price for her goods while, at home, her neighbors, either passively or actively, get involved in protecting her. Before long we’re watching urban crooks pursue our heroine while the local constable, searching for salmon poachers, threatens to stumble upon the enterprise and outside bankers show up to seize Grace’s property; for good measure the ladies’ gardening society, composed of birdlike old biddies, gets drawn into the scheme, with two of their members brewing up some of the weed in the misconception that the plants are some esoteric sort of tea and feeling the inevitable consequences. There are shades of “The Ladykillers” at work here, and even a touch of such American whimsy as “Arsenic and Old Lace.”

In this instance, however, all of the colorful characters and intricate situations have a decidedly contrived, second-hand feel to them, as if the makers were too consciously trying to mimic a genre native to a more innocent, naive time. “Saving Grace” follows the formula of the old Ealing comedies, but it does so in a terribly calculated way, with a smoothness that has the aroma of a Hollywood conference room rather than a stuffy London club; you can almost feel the underlying drive to fashion the next “Full Monty.” Perhaps the most obvious example is that while the script follows the old convention that criminal activities, no matter how benign, can’t actually be allowed to save the day, the writers nonetheless feel compelled to tack on a happy ending that comes out of left field and is both derivative and disappointing.

Still, the picture leaves a pleasant enough aftertaste, especially because of its estimable cast. Blethyn, who can play farce and drama with equal aplomb, makes a funny and sympathetic central figure, and Ferguson is an amiable slacker. Martin Clunes adds many humorous touches as the local doctor with a taste for reefers, while Ken Campbell strikes the pose of a Gilbert-and-Sullivan flatfoot as an apparently bumbling police sergeant. The secondary performers are at least adequate, though Tcheky Karyo is overly constrained as a silky drug lord and Cole gives the elderly garden-society ladies–particularly the two who get high on hemp tea–too much leeway for shameless mugging.

As a modern attempt to recapture the magic of the Ealing formula, “Saving Grace” isn’t as successful as 1998’s “Waking Ned Devine,” whose very title it copies. Still, enough of the old effervescence remains to leave a viewer at least somewhat giddy from its concentrated whimsy. And you don’t even need to light up to get the effect.