Lisa Cholodenko's sexy, comic drama lacks the finesse and clarity of her debut feature, the lesbian romance High Art, but is not without reward.

Harvard medical school graduates Sam (Christian Bale) and fiancé Alex (Kate Beckinsale) find their sober, sensible values challenged when they go to stay with Sam's free-spirited rock producer mum, Jane (Frances McDormand), in her pad in the titular Laurel Canyon, a sun-drenched, leafy spot in the LA hills.

Sam, who has rebelled against his hell-raising mum by being as square as possible, is mortified to find on arriving that he and his mousy partner must share the house with Jane and her laddish English rock group, all in full party mode - they are in the process of recording an album. Jane is also bedding lead-singer Ian (Alessandro Nivola).

When Sam starts daily work at the local hospital, Alex finds herself leaving her room and her dissertation on the sex-life of fruit flies, to idle away hedonistic hours downstairs with the band. Before long, it's threesomes in the swimming pool. Meanwhile, Sam finds himself flirting with a supervisor (wide-eyed siren Natascha McElhone) at the hospital where he is resident.

It is an intriguing enough set-up, but the complex liaisons and associated, and admittedly tricky, issues are cut short as the plot turns pedestrian. Whether director Lisa Cholodenko didn't have anything more to say, or felt there wasn't enough time to go deeper, who knows? Whatever, the languid mood doesn't make up for a drawn-out and thin story, with little to say.

The dialogue also creaks at times, which is a shame, because the performances are good. Okay, the ever-so-pert Kate Beckinsale's scholarly turn doesn't quite ring true, but Alessandro Nivola is entertaining as the roguish Ian and Frances McDormand plays the ageing rock babe to the hilt.

As you douse in Californian sunshine, there are also surprises that come at you. Like the ending. I don't know if it was planned or forced by circumstance, but it is inspired.