Former boxer and drug mule Bradley Thomas (Vince Vaughn) finds himself in a precarious situation after losing his job at an auto-repair shop. Upon returning home, he discovers his wife, Lauren (Jennifer Carpenter), in her car, chatting with someone on her cellphone. As Bradley draws nearer, he notices a love bite on her neck, prompting Lauren to confess her infidelity. Enraged, he forces her inside the house and subsequently destroys her car with his bare hands. Once he calms down, they sit to discuss their troubled relationship, leading Bradley to forgive Lauren and return to the dark world of drug smuggling.
Fast forward eighteen months, and Bradley and a now pregnant Lauren have upgraded to a larger, more luxurious home. His boss, Gil (Marc Blucas), introduces him to Eleazar, a new business associate, presenting Bradley with a new assignment. The job entails sailing offshore with two of Eleazar's men to collect a package of crystal meth. Despite his suspicions about one of the men, Roman (Geno Segers), Bradley accepts the job after being promised three months of paternity leave. However, as they arrive at the pier, Bradley senses an operation by the police and urgently instructs his companions to ditch the contraband. While the two men disregard his warning and engage in a shootout with the police, Bradley turns his weapon against them, ultimately resulting in his arrest and a seven-year sentence in a medium-security prison.
The situation escalates dramatically when, on the second day of his incarceration, Lauren is abducted by operatives working for Eleazar. Soon after, Bradley is approached by the Placid Man (Udo Kier), who delivers a chilling ultimatum: in order to save his unborn child, Bradley must assassinate an inmate named Christopher Bridge, located in the maximum-security Redleaf Correctional Facility. With little choice, Bradley agrees to the grim task.
Determined, Bradley orchestrates a confrontation with the guards that lands him in Redleaf, where he meets the harsh Warden Tuggs (Don Johnson). His new cell is a nightmarish space, complete with a grotesquely clogged toilet. Eventually, he learns from a fellow inmate that Christopher Bridge is not even in the facility, prompting him to fight his way into the dreaded cell block 99, where the most notorious criminals are kept. Here, Warden Tuggs enforces brutal punishments, including a shock belt that Bradley is forced to endure as a consequence of a fight.
In cell block 99, Bradley discovers the horrifying truth: the vicious gang led by Eleazar is toying with him, and he is subjected to endless torment. However, using his wits, Bradley meticulously devises a plan to thwart his captors. By crafting a barrier against the shocks, he ambushes Wilson (Tom Guiry) and gains the upper hand, leading to a violent confrontation with Eleazar and his henchmen. In a brutal showdown, Bradley exacts revenge and captures Eleazar, even as he learns that Lauren's safety hangs in the balance.
A frantic negotiation ensues, followed by a deadly series of events that sees Bradley hold Eleazar hostage, awaiting confirmation of his family's safety. As tensions peak, the fate of all involved hangs precariously as he battles Warden Tuggs and his men. With the clock ticking, he makes one final threat before turning to meet his fate head-on.
In a profoundly emotional climax, Bradley speaks to his family one last time before expressing his vengeance against Eleazar in a grisly act. Just as he surrenders to the inevitable, he reflects on his remaining moments, leading to a tragic conclusion that leaves viewers stunned as chaos reigns in the prison.
