By Mike Collett-White

VENICE (Reuters Life!) - The Coen brothers' latest film, the madcap comedy "Burn After Reading", has sharply divided the critics, unlike last year's acclaimed "No Country For Old Men" which won four Oscars including best picture.

Early reviews of the eagerly-awaited picture have begun to appear following its world premiere at the Venice film festival on Wednesday, which brought A-listers George Clooney and Brad Pitt, and hundreds of screaming fans, to the red carpet.

Trade paper Variety panned the comic spy spoof, calling it a "flame-out".

"Nothing about the project's execution inspires the feeling that this was ever intended as anything more than a lark, which would be fine if it were a good one," wrote Todd McCarthy. "As it is, audience teeth-grinding sets in early and never lets up."

Many of the warm words he had for "Burn After Reading" were reserved for Pitt, appearing in a Coen film for the first time.

Like several other critics, McCarthy praised Pitt's portrayal of a naive, hyperactive gym instructor who tries to extort money from a sacked CIA analyst whose sensitive memoirs he stumbles across when a computer disc is dropped by accident.

"Pitt slices the ham very thick indeed, but uniquely emerges as endearing in doing so," he said.

At the other end of the scale was Screen International's Lee Marshall, who called the movie "a beautifully produced mix of spy story, U.S. zeitgeist satire and relationship drama.

"('Burn') is a smart urban screwball comedy about the perils of idiocy that uses its all-star cast to dazzling and often hilarious effect."

Wendy Ide of the Times in London gave the film four stars out of five, and singled out Pitt and John Malkovich as the best performances.

Malkovich is the heavy-drinking, aggressive CIA analyst, while Clooney, appearing in his third Coen movie, plays an exercise-obsessed federal marshall who cheats on his wife.

Ide's main reservation is that the cast of characters it would be fair to describe as idiotic fails to elicit much sympathy in the audience.

"It would perhaps be more rewarding if we could like the characters as well as laugh at them," Ide concludes.

Kirk Honeycutt of The Hollywood Reporter, in a mixed review, calls "Burn" "a minor piece of silliness with all the trappings of an A-list studio movie."

In conclusion, he quotes a line from a CIA officer in the movie who has just been told about the baffling series of events surrounding the missing memoirs.

"Report back to me when it makes sense."

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