Tom Wilkinson in Michael Clayton.

“This is not just madness,” attorney Arthur Edens says in the opening moments of Michael Clayton, shortly before we learn that he stripped naked while discussing the settlement terms of a $3 billion class-action lawsuit. “Madness” is of course a relative term, and it’s a credit to writer/director Tony Gilroy that Arthur is probably the sanest character in a world where right and wrong are often replaced with dollar signs.

Edens (Tom Wilkinson) works for one of the largest and most powerful firms in New York City, and he’s having a crisis of conscience because his client, a company called U/North, is about to get off easy with a settlement after polluting and killing small family farms. Enter Michael Clayton (George Clooney), the firm’s problem solver — or “janitor,” as he calls himself — who specializes in spinning negativity that could potentially damage the firm’s image and reputation.

But, when even he can’t handle his old friend Edens, his boss (Sydney Pollack) and U/North lead counsel Karen Crowder (Tilda Swinton) do whatever it takes to make sure the settlement occurs as planned. As the layers of corruption unfold, Michael finds credence in Arthur’s ramblings and becomes a casualty of a world that he helps to sustain.

Following Clooney through Clayton’s journey is yet another validation of the actor’s evolution from the “sexiest man alive” to a bona fide leading man. Clayton’s calm, embattled demeanor as he fends off duplicitous corporate execs and deals with an array of personal issues makes him as compelling a character as we’ve seen all year. He may be just as unscrupulous as the people he works with, but the story demands that we like him and, thanks to Clooney, we do. The rest of the ensemble cast is just as strong, and don’t be surprised if Wilkinson earns an Oscar nomination for best supporting actor.

Still, Gilroy, who co-wrote all three Bourne films, makes a crucial mistake that keeps the film from being a first-rate drama. Gilroy unnecessarily uses the cinematic crutch of revealing a piece of the ending early on, then flashing back four days and working up to that point in the normal flow of the movie. This gimmick undermines the suspense because viewers are distracted by thoughts of events that we know come later. A conventional beginning-middle-end storyline would’ve served the drama better.

A better, smarter movie also would have left Clayton’s personal issues (he’s $75,000 in debt, estranged from his son, etc.) out of the story and focused on how he’s an expendable pawn for his avaricious firm. While the personal problems make his situation more turbulent, they don’t add anything to the sociopolitical bite the film takes out of corrupt big businesses and the lawyers who keep them running.

How ironic that, in a movie about coverups and lies, the main flaws are so obvious that they can’t be overlooked. But, given the strength of the acting and the gripping drama, that’s not enough to take Michael Clayton — neither the man nor the movie — too far off track.