The Informant! is based on the saga of real life corporate whistleblower Mark Whitacre, played by Matt Damon. Whitacre was involved in a price-fixing scheme at the agribusiness giant Archer Daniels Midland. He agreed to tape his colleagues for the FBI— part of his own grandiose scheme to win promotion. The stress of his undercover ordeal worsened Whitacre’s bipolar disorder, which was later diagnosed and treated.