A rogue group of U.S. Marines led by a highly decorated, but disillusioned, Brigadier General takes over Alcatraz Island, threatening to launch rockets filled with deadly VX gas upon San Francisco unless the government pays ransom and acknowledges the soldiers who died under covert operations. The situation escalates quickly, with the lives of millions at stake, putting the government in a precarious position. Desperate for a solution, the authorities turn to an unlikely pair: a mild-mannered chemist from the FBI's chemical weapons team, who has never seen combat, and a British national imprisoned for decades, the only man ever to escape Alcatraz. Together, they form an unconventional team tasked with the impossible mission of infiltrating the impregnable fortress and disarming the missiles.

The chemist and the escapee must quickly find a way to work together, despite their vastly different backgrounds and ideologies. As they stealthily move through the labyrinthine corridors of the former prison, they encounter various traps and a relentless group of Marines determined to protect their cause at all costs. The duo's unique set of skills complements each other in unexpected ways, fostering a begrudging respect and partnership. With time running out, they must navigate the complexities of the fortress, disarm the biochemical weapons, and thwart the potentially catastrophic attack, all while dealing with the moral implications of their acts and the realization of what they're truly fighting for.