Entertainment

Mattletale!

MATT Damon is goofy perfection as a corporate whistleblower with a secret life and serious credibility issues in “The Informant!,” Steven Soderbergh’s playful companion piece to “Erin Brockovich.”

Loosely based on one of those true stories that’s wilder than fiction, it presents Damon (who gained 30 pounds for the role) as the real-life Mark Whitacre, a research chemist who was rising rapidly through the executive ranks at the agribiz giant Archer Daniels Midland in the early ’90s.

When he blames production problems on sabotage by a Japanese competitor demanding a $10 million extortion payment, ADM calls in the FBI and orders Whitacre to cooperate.

Does he ever, volunteering to a pair of flabbergasted special agents (Scott Bakula, Joel McHale) that ADM has engaged in a massive price-fixing conspiracy with competitors around the world.

Whitacre readily agrees to wear a recording device to tape incriminating meetings and begins calling himself “Agent 0014,” because he’s twice as smart as James Bond.

When the indictments come down after a couple of years, the FBI agents learn Whitacre’s also 10 times as crooked. He’s squirreled away millions of ill-gotten dollars in accounts around the world, even as he kept assuring the FBI that “I’m one of the good guys.”

Seriously delusional and quite possibly bipolar, Whitacre hopes to take over as CEO of ADM when his bosses are busted.

The tipoff that Whitacre is not the hero he presents himself is in the title’s exclamation point, as well as his rambling, free-associative narration that frequently veers from the story line into his personal obsessions, including his collection of sports cars.

And then there’s the infectious, ’60s-style score by Marvin Hamlisch, which at times appears to recycle bits and pieces of music from his two Woody Allen movies, “Take the Money and Run” and “Bananas.”

Damon shows terrific bravado in the lead role, leading us through a tricky script by Scott Burns (“The Bourne Ultimatum”) based on a book by New York Times investigative reporter Kurt Eichenwald.

Melanie Lynskey does well with the challenge of playing Whitacre’s oblivious wife, who never questions his wild assertions and who, we are told, was waiting for him after he served nine years in prison.

“The Informant!” is more amusing than laugh-out-loud hilarious, but is never boring. It’s certainly a lot more fun and entertaining than Soderbergh’s last two films, the deadly serious “Che” and “The Girlfiend Experience.”

lou.lumenick@nypost.com