The Informant! is an offbeat, funny movie based on a true story. It imitates the visual style and musical score of a 1970s crime caper movie, perhaps because that’s what the protagonist thinks he’s involved in.

Mark Whitacre (Matt Damon) is one of the top executives at agribusiness giant Archer Daniels Midland (ADM). He is under pressure to figure out why the new lysine factory is failing to produce enough lysine (an agricultural feed additive.) He tells them that he has been contacted by an extortionist who says that the plant is being sabotaged by an industrial spy.

ADM calls in some FBI agents (Scott Bakula and Allan Havey). Whitacre ends up telling them that he made up the story of the extortionist, but that the top executives at ADM are involved in a massive international price-fixing conspiracy involving just about every additive that can be extracted from corn, from lysine to high-fructose corn syrup. He agrees to act as an undercover informant to gather evidence of the conspiracy.

The story is given a weirdly comic tone by Whitacre’s constant stream-of-consciousness voice-overs, which at one level seem bland, but at another level are off the wall. The FBI agents only belatedly realize that Whitacre, who seems the very model of an ordinary, upstanding citizen, is actually a nut, though the price-fixing conspiracy is very real.