After the international triumph of No Country For Old Men, Joel and Ethan Coen modestly predict a much more difficult time for their new comedy thriller, on the basis that lightning seldom strikes twice.

Written at the same time as their Oscar winner but produced after, it isn't in truth anything like as outstanding a movie. But with half a dozen stars attached, it ought to make a few waves, especially since they play mostly against type, with notable panache.

The story has John Malkovich as an ousted and frequently drunk CIA analyst whose wife (Tilda Swinton) is having an affair with George Clooney's married federal marshal. She loses the outline of a book her husband is writing about the CIA as revenge for his sacking in Hardbodies Fitness Centre. There, Brad Pitt's instructor finds it, shows it to his fellow employee, played by Frances McDormand, and, thinking it contains state secrets, tries to blackmail the analyst.

When he refuses to pay, the two attempt to sell it to the Russians after which events spiral well out of everybody's control, with murder included.

The great thing about the movie, which takes the mickey out of the CIA, fitness centres, plastic surgery, illicit sex and a lot else besides, is the way it is performed.

McDormand is as marvellous as usual as Linda Litzke, the fitness centre employee who wants the money to make herself a new and more attractive person and makes desperate eyes at the men she meets off the internet totally unaware that Richard Jenkins, boss of Hardbodies, is desperately in love with her.

But the surprise is Brad Pitt's bubblebrainedfitness instructor in tight Spandex shorts and with a streaked bouffant hairdo that he'll want to get rid of as soon as possible. This is a turn the accuracy of which proves his credentials as a fine comedy actor not averse to being self-deprecating.

Malkovich too has a great deal of fun with the part of the hard-swearing, drunken analyst as does Clooney as the nerdish federal marshal, while Swinton's portrait of a nagging wife and equally irritated mistress is one of her small masterpieces.

So what's to dislike about the movie? Well, it doesn't actually hang together all that well despite its sharp script and fine playing. In the end, it seems like a minor strut in the Coen brothers' canon, but very enjoyable for all that.