Roz (Robin Wright) and Lil (Naomi Watts) have been best friends since childhood. Physically and emotionally close, the two women are also work colleagues and spend most of their free time together, to the extent that Lil's husband Harold (Ben Mendelsohn) has started to feel excluded from their partnership. Ageing gracefully and spiritedly, the women have matching beautiful homes on a beautiful stretch of the Australian coast. And they even have matching beautiful sons, Ian (Xavier Samuel) and Tom (James Frecheville), who – wouldn't you know – have grown up to be best friends, too. With Roz widowed and Harold away working in Sydney, the mothers and their sons have become a fairly exclusive foursome. Ian has developed intense sexual feelings for Roz, which end up being consummated one night. The encounter is observed by Tom, who, motivated more by spirit of "anything you can do..." than by genuine lust, ends up seducing Lil shortly afterwards.

Based on Doris Lessing's story The Grandmothers, Anne Fontaine's Adore presents itself as a provocative, grown-up drama about illicit desire. But, after a relatively promising opening section (which economically sketches Roz and Lil's teenage closeness, the death of Roz's husband, and their sons' friendship), the movie becomes increasingly unconvincing in its developments and, at times, rather risible. Fontaine gives the film a superficially enticing, limpid look, making the most of the attractive beach locations. But she's hampered throughout by a very poor script by Christopher Hampton that's full of clunky, over-explanatory dialogue. "What have we done?" wonders Roz when the parallel affairs come to light. "Crossed a line," confirms Lil, a remark that deservedly drew derisive giggles at yesterday's press screening.

Clearly Fontaine and Hampton are congratulating themselves for not passing judgment on Roz and Lil's conduct and for not having the women's interaction become some Bette & Joan-style bitchfest. But Roz and Lil's endlessly supportive, sisterly rapport – the understanding with which they approach one another about the affairs, the constant checking in to see how the other is "feeling" – seems equally false (not to say mighty sentimental) by the end.

There's the strong suggestion that the affairs are actually a way of vicariously acting out other suppressed desires: the mothers' for each other; the sons for their own mothers etc. But the movie doesn't explore this notion deeply. Instead, Fontaine resorts to posing the actresses like Bergman heroines in two-shots that emphasise just how noble and sensitive the characters are, despite their questionable conduct. The glossiness of the movie's approach starts to wear thin: the gorgeous location, the fact that the sons are perfect physical specimens without so much as one teenage blemish – all if this seems a very bogus way of making the tacky, overly symmetrical plot more palatable. 

The excellent Wright brings some interesting tension and suggestions of conflict to her woman-of-infinite-wisdom role. And if Watts's performance degenerates into a series of weepy close-ups she has a few resonant moments, such as an early bop to Kirsty MacColl's "In These Shoes?" There are, indeed, some scattered strong sequences throughout: a shot of Lil critically observing herself in a bathroom mirror; the tingling eroticism of her first encounter with Tom; a fine final tableau. But these moments are all silent. Adore may think it's being wonderfully transgressive by placing the desires of older female characters centre stage. But the movie fails because when it comes to finding language to insightfully articulate and explore those desires Hampton's dialogue is totally inadequate to the task.  

Oct 10, 2013: 12:00: VUE7

Oct 11, 2013: 18:00: VUE5

Oct 13 2013 : 15: 30: Cine Lumiere

Adore at the London Film Festival , at Vue West EndAlex Ramon reviews Adore at the London Film Festival.2