George Clooney is totally convincing in his downbeat hero role in 'Michael Clayton'

(Editor's Note: This review has been changed since it was first published to correct a reference to the first name of director Tony Gilroy and to remove a reference to "Klute" (1971) as a post-Watergate (1972-74) film.)

George Clooney's annual fall bid for liberal seriousness and Oscar glory this year is "Michael Clayton," and he and director Tony Gilroy claim it's designed to be a '70s-style paranoid thriller in the tradition of "Parallax View" and "Chinatown."

As a point of historical accuracy, it should be noted that the film really doesn't follow through on this ambition, since those great post-Watergate thrillers usually did not end with the hero slaying the dragon and everything being neatly resolved.

Still, though the film ultimately bows to the smiley-face demands of the New Millennium box office, it manages to be a spellbinding action-drama, skillfully built upon a scary corporate conspiracy, chock-full of enjoyable downbeat performances.

The title character (Clooney) is a burned-out, gambling-addicted, divorced father who works as a "fixer" for a powerful Manhattan law firm. In an effort to free himself of this life he opened a trendy restaurant, but it failed. After a prologue ends with an attempt on his life, the movie flashes back four days to tell the story of how he's called in to clean up the complex mess that ensues after one of the firm's top attorneys (Tom Wilkinson) has had a freakout in the midst of a deposition.

In the process of this, he finds evidence that the firm's client in the case, a huge agrochemical company, may have recklessly endangered the health of an entire Wisconsin community -- and this both pushes him toward a moral crisis and puts him in the cross hairs of the company's assassins.

Reportedly, Clooney wanted to direct the film but screenwriter Michael Gilroy ("The Bourne Ultimatum") held out for the job. At times, Gilroy's inexperience shows, and his script might have skipped the long, climactic action sequence that asks us to feel suspense about an outcome that was revealed in the prologue.

But he otherwise gives the movie a frantic energy, a breathless pace, a dense atmosphere of corruption, plenty of snappy dialogue, and an ensemble of morally compromised supporting characters wonderfully played by Wilkinson, Tilda Swinton and Sydney Pollack (director of the iconic '70s paranoid thriller, "Three Days of the Condor.")

"Michael Clayton" also makes a strong showcase for Clooney. The role is humorless and he looks grayer and more rumpled than ever, but he's totally convincing. He somehow makes the stressed-out, world-weary character as appealing as Bogart at his best, and the movie is one of his more irresistible star turns.