In this action thriller, Nick Adams, an agent for the Bureau of Alcohol, Tobacco & Firearms, goes undercover to enter a prison run by the tyrannical but efficient warden, Pike. He does this after his partner is killed doing undercover work in the same prison. The prison presents a harsh environment and fighting between inmates is rampant. Luckily, Adams was trained to fight in the Marines and he can take on any of them. But then his nemesis Jimmy Wong, a prominent mob leader, enters the facility. There the crooked wheeler-dealer has set up a gun-running arrangement with prison officials who let him have the run of the place. Wong uses this to exact his revenge on Adams. Action ensues, culminating in a prison break where the two fight it out while hanging from a fleeing helicopter.