The actress's directorial debut, 2002's Looking for Jimmy, featured a lot of (sometimes self-involved) talk, but it had some promise about it; her follow-up, along with her work on the screenplay for 2004's Before Sunset, suggests she's finally found a voice to sustain such talk. In several ways, 2 Days forms an extension of those scenes in Sunset's first half: the sparky, pointed jousting between lovers on either side of the culture war. Her antagonists are Marion (Delpy herself), who grew up in the city, and Jack (Adam Goldberg), a touchy American photographer who speaks not one word of French. After two years together, the pair are on a two-day stopover in the city of love after a disastrous trip to Venice, where Jack came down with gastroenteritis.
In Paris, they will face trial by, in order of appearance, French plumbing, "kids-size condoms", fat cats, a succession of variously offensive cabbies, and the fact that Marion appears - at least in Jack's eyes - to have slept with every single man in their particular arrondissement. The film's subject is not, then, the usual romcom rigmarole of meeting-cute and finding true love - Jack and Marion are, we gather, long over that illusion - but the everyday jealousies and passive-aggressive moves anyone who's in a relationship has had to work hard to overcome. (As Marion puts it in her opening monologue: "Two years - these days, it's almost a miracle.")
Liberated of the need to appear ingratiating, both leads have tremendous fun. Practically the first thing Jack does on screen is to knowingly misdirect a party of Da Vinci Code fans into the Parisian suburbs: "Maybe they'll see a riot". Goldberg has a particularly good rant delineating Jack's thoroughly American attitude in the matter of personal property, and even makes comic sense of a scene where the character whines about the objectification of men whilst being mounted by Julie Delpy. The latter, meanwhile, effectively gets to send up her often over-sensitive screen image as a very modern girl, roping in her own parents (Albert Delpy and Marie Pillet) to play, respectively, a sex-crazed vandal and a former lover of Jim Morrison.
We've seen too many Meet the Parents-influenced, lukewarm culture clashes in recent years, but as a director, Delpy arrives at something new and fresh-seeming by splicing in elements of Woody Allen and the earlier, more playful Godard films; there's an encounter between Marion and a former boyfriend of hers, a sex tourist with paedophilic urges, that's as remarkable a scene as I've seen in a comedy for some time, as serious in its intent as it is comic on the surface. Cross-fertilising the personal and the political with a lot of laughs, it's a very appealing proposition: for once, we're faced by a romantic comedy with clear eyes and all of its own, mostly very sharp teeth.
2 Days in Paris screens on BBC2 tomorrow night at 11.30pm.