Middle-aged lawyer Michael Clayton (George Clooney) is a "fixer" who clears up complex or dirty cases on behalf of corporate clients. But he has a number of personal and professional problems. His family life is messy; he's a lone parent, his brother has run up large debts, he's struggling with a gambling problem, his career appears to be going no-where - and he has become tired of fixing other people's mistakes.
An old friend and colleague, Arthur Edens (Tom Wilkinson), has been working on an important case on behalf of a large client for eight years but the case is not going well and his friend's behavior is causing concern. Clayton is called in to fix the problem.
As he discovers more about the case, Clayton realizes that the defendants' case is correct and when his friend (Edens) dies, Clayton himself becomes a target for the dark forces that defend corporate interests.
Clayton narrowly survives an assassination attempt (when his car is blown up) and confronts one of the company directors, Karen Crowder (Tilda Swinton), with evidence of corporate malpractice. She offers to buy his silence but he is recording the conversation and she is arrested.
Tom Wilkinson ... Arthur Edens
Michael O'Keefe ... Barry Grissom
Sydney Pollack ... Marty Bach
Danielle Skraastad ... Bridget Klein (voice)
Tilda Swinton ... Karen Crowder
George Clooney ... Michael Clayton
Wai Chan ... Chinese Dealer
Alberto Vazquez ... Player #1
Brian Koppelman ... Player #2
Thomas McCarthy ... Walter (voice) (as Tom McCarthy)