In 1964, a brash, new pro boxer, fresh from his Olympic gold medal victory, explodes onto the scene: Cassius Clay. Bold and outspoken, he cuts an entirely new image for African Americans in sport with his proud public self-confidence and his unapologetic belief that he is the greatest boxer of all time. Yet at the top of his game, both Ali's personal and professional lives face the ultimate test.

Depression-era bank robber John Dillinger's charm and audacity endear him to much of America's downtrodden public, but he's also a thorn in the side of J. Edgar Hoover and the fledgling FBI. Desperate to capture the elusive outlaw, Hoover makes Dillinger his first Public Enemy Number One and assigns his top agent, Melvin Purvis, the task of bringing him in dead or alive.