In Depression-era America, John Dillinger is a notorious bank robber considered a hero by many for his daring heists and escapes. As the leader of his gang, Dillinger masterminds a series of high-profile bank robberies, becoming the top target of J. Edgar Hoover's fledgling FBI. The government agency is determined to bring down Dillinger and his associates, employing advanced methods of crime-fighting that mark the beginning of modern law enforcement. The public's fascination with Dillinger's exploits grows, even as he enjoys the spoils of his crimes, living openly and lavishly, convinced of his invincibility.

Melvin Purvis, a sharp and determined FBI agent, is tasked with capturing Dillinger. As Purvis and his agents begin to close the net around Dillinger, a captivating game of cat and mouse unfolds. Dillinger, ever resourceful, continues to elude capture through a combination of clever planning and sheer audacity. The chase intensifies, drawing in various allies and enemies, from fellow crooks to the women who love them, against the backdrop of a nation struggling under economic hardship. As the lines between criminal and lawman blur, both Dillinger and Purvis are forced to question their means and motivations in a world where loyalty is fragile, and betrayal is all too common.