It is now clear that filming in Britain brings out the worst in Woody Allen - or at least makes painfully clear just how tin-eared and clueless he can be when attempting to depict a culture outside his own. His last film to open in the UK, You will meet a tall dark stranger, was arguably worse than Match Point, Scoop and Cassandra's Dream. All four featured the usual clunky cultural name-dropping (a mention of Modigliani here, a reference to Proust there), but were irredeemably uninspired. Fortunately for his fans, Allen proved that he is not washed up with Whatever Works and Vicky Cristina Barcelona.

Midnight in Paris is not up there with the latter, and has been wildly overpraised in America, but it still represents a vast improvement on Allen's British films. A fable about a writer who wishes he belonged to another time and place - specifically Paris in the 1920s - it is often charming and funny. It features Owen Wilson doing a surprisingly good turn as the usual Allen-ish protagonist and boasts the gorgeous Marion Cotillard - at 36 a superannuated love-object by Allen's standards - as his love interest.

Owen plays Gil, a hack Californian screenwriter visiting the City of Light with his high-maintenance fiancée Inez, played by Rachel McAdams (who seems to have replaced Scarlett Johansson as Allen's latest young crush). Her philistine parents are also in town, as is her old crush Paul (Michael Sheen, excellent as a pretentious pedant).

One evening Gil is walking around by himself when a clock strikes midnight and an antique car pulls up. The passenger invites him to a party and Gil finds himself back in time, at a Left Bank bar with members of the so-called lost generation of expat Americans. Scott and Zelda Fitzgerald take him to meet Ernest Hemingway and then to a party where Cole Porter is playing the piano and Josephine Baker is dancing.

Gil tells Hemingway about the novel he himself is writing and Hemingway offers to show it to Gertrude Stein. Gil rushes out to get the manuscript from his hotel only to find himself back in 2010. The next night however, the car reappears on the same corner at midnight and Gil gets to meet Picasso, Buñuel and also their beautiful (mythical) muse Adrianna (Cotillard). She and Gil are drawn to each other but she herself dreams of living in the Paris of the 1890s.

The Paris the characters wander through is the cliché Paris of tourist brochures: the Champs Elysees and Ile St-Louis. For Allen the city is merely a backdrop for his American characters and often crudely conceived historical figures. It is probably just as well that he does not attempt to evoke French people or portray any real aspect of Parisian society.

For most of its brief length Midnight in Paris is frothy fun. Almost the only thing that threatens to spoil its sweet romance and its interesting idea about the perils of nostalgia are the filmmaker's sometimes heavy-handed attempts to prove that, despite being a college drop-out, he is a cultured fellow.

(All the superficial middle-class, middle-brow cultural name-checking certainly worked a treat in the US where audiences and critics apparently felt flattered to be treated as the sort of people who have heard of Buñuel or Dali.)

There are also moments when a certain unattractive kind of New York smugness creeps into the film - the same kind that permeated Le Divorce, the James Ivory adaptation of Diane Johnson's novel of Americans in Paris. Both feature a leading character who reflects the filmmakers' sense of themselves as a superior kind of American, the kind who really understands "Europeans", unlike his or her crass in-laws. In this case, the Allen character's in-laws are not only philistines who prefer hamburgers to haute cuisine, but also in case you don't fully get the class message, Republicans and Bush-supporters.

It makes it all the more ironic that Allen clearly knows little about the cultural figures who populate the time-travel sequences. At one point he has his crudely drawn Hemingway lecture Gil about big-game hunting in Africa, even though the twentysomething Hemingway only went to Africa many years later.