Vital signs

Early on in Michael Clayton, there's a moment of metaphorical genius when we meet Karen Crowder, one of the bent lawyers who populate this impressive legal drama. Slumped in a lavatory stall at U/North - the agrochemical company facing a multimillion-dollar class action suit at which she is chief consul - Crowder pulls herself to a nearby washbasin and looks up. 'Which is the thing we always ask about these people,' says Tilda Swinton, who plays Crowder.

'How do they face themselves in the mirror in the bathroom every morning?'

Crowder isn't the only one having to come to terms with herself in the film. Played by George Clooney in less-than-gorgeous mode, Michael Clayton is an in-house fixer for Manhattan corporate law firm Kenner, Bach & Ledeen, meaning he toils behind the scenes cleaning up clients' messes in a life of perpetual damage limitation. This, along with mounting debts from an out-of-control gambling habit and a failed business venture, means the divorced Clayton is already an empty husk of a man when we meet him. By the time he becomes embroiled in the U/North case, he must join Crowder, looking in that mirror at an ugly reflection.

Debut director Tony Gilroy, best known for his work writing The Bourne Identity and its two sequels, first thought about writing Michael Clayton when he was researching his 1997 script for Taylor Hackford's The Devil's Advocate. Frequently meeting with lawyers as he sketched the character of Clayton, he says his protagonist remains a composite. 'I've never met anybody who does exactly what Michael Clayton does. It's not exactly something a law firm goes out and advertises,' he says.

And although the film is inspired by real lawsuits, such as the infamous Anderson versus General Motors case in the 1970s, he sounds a note of caution. 'I'm wary of making the movie issue-based.'

Swinton also met lawyers in preparation for her role. 'I realised that world exists and that it's as opaque and hallucinogenic as it looks,' she says. 'They speak a language that I don't even think they understand. And a lot of them are obsessed with shoes and all sorts of other things.'