Michael "Mike" Ventura was a former employee of Longitude Pharmaceuticals. He lived on a compound in Itta Bena, Mississippi, complete with a private dock on the Black Brake swamp. A former county sheriff and security director at Longitude Pharmaceuticals, Ventura was a strongly-built, sinewy man with receding hair. He was a wealthy sportsman, but also a bigot, well-known and respected by the regulars at Tiny’s Bait ’n’ Bar, widely recognized as “one of the last places where you didn’t have to look at jigaboos, faggots or Yankees."Ventura was part of Project Aves, and played a vital role in the coverup following the Doane family incident and subsequent fire at Longitude. After the project secretly relocated to Spanish Island, he became its only lifeline to the outside world, bringing supplies to the remote swamp location for the next decade.
When Special Agent Pendergast and Vincent D’Agosta began looking into the circumstances of his Helen Pendergast’s death and got closer to the truth about Longitude and Project Aves, Judson Esterhazy called on Ventura for help. Esterhazy’s attempt at assassinating Pendergast outside Penumbra Plantation had instead sent D’Agosta to the hospital, prompting Laura Hayward to take his place in the investigation. With Pendergast and Hayward poised to head out into the swamp in search of Spanish Island, Ventura used his influence with the denizens of Tiny’s Bait ’n’ Bar, appealing to their deep-rooted resentment of environmental agencies that had shut down the town's logging industry and severely damaged the hunting and fishing businesses by turning half of the Black Brake swamp into a wildlife refuge and wilderness area. He convinced them that Pendergast and Hayward were undercover environmentalists looking to turn the rest of the swamp into a protected wildlife area, whipping them into a frenzied mob. The next day, Ventura waited anxiously in the parking lot of the Bait ’n’ Bar for the return of the raiding party, but the somber, beaten crew that returned to the docks was not what he had been expecting: they had successfully ambushed Pendergast and Hayward, disabling their airboat, tossing their law enforcement IDs into the swamp and humiliating Hayward, but Pendergast had managed to disarm them after severely injuring their leader—Bait ’n’ Bar proprietor Tiny himself, who quickly gave up Ventura’s name as the one who had incited them. The mob itself turned on Ventura upon their return, furious about being misled about Pendergast and Hayward’s identities; he was forced to flee the area and regroup with Esterhazy.
Ventura and Esterhazy decided to take matters into their own hands, returning to the swamp themselves to intercept Pendergast and Hayward before they could reach Spanish Island and uncover the truth about Charles Slade and Project Aves. In the ensuing showdown, Ventura was shot in the shoulder and held at gunpoint by Hayward. When she began to question him, he was shot again—fatally this time—by Esterhazy, ostensibly to keep him from revealing his identity.