Martin J. "Marty" LaHart (December 22, 1899-July 2, 1975) was a FBI agent and a member of "The Untouchables" group of agents which included Eliot Ness. Lahart, an ex-Marine, was a Irish-American, his career and life story became inspiration for the fictional Jimmy Malone character, who was a Chicago police officer that was used in the critically acclaimed crime drama film The Untouchables, which starred Kevin Costner as Ness, and Sean Connery as the Malone character.