In a tragic home invasion in 1999, Clyde Alexander Shelton, portrayed by Gerard Butler, witnesses the brutal murder of his wife and daughter at the hands of Clarence James Darby (Christian Stolte) and his accomplice Rupert Ames (Josh Stewart). When the prosecutor, Nick Rice, played by Jamie Foxx, struggles to secure a solid conviction against the criminals due to a lack of DNA evidence, he makes a controversial deal with Darby for a lesser charge in exchange for his testimony against Ames. Ames is convicted and sentenced to death, while Darby is soon released, leaving Shelton feeling deeply betrayed by the justice system.
Fast forward ten years, as Ames faces his execution, a sinister plan unfolds. The usual deadly drug administered has been replaced with an anti-convulsant, leading to Ames enduring an agonizing demise. Evidence surfaces that suggests Darby may have tampered with the execution process. As the police close in, an anonymous caller directs Darby to a remote location—only to reveal himself as Shelton, disguised as a police officer. With revenge fueling his actions, Shelton immobilizes Darby using puffer fish venom and gruesomely dismembers him while recording the act for posterity.
When Darby’s remains are discovered, circumstantial evidence points toward Shelton. Aware of the flimsy nature of this evidence, he turns himself in and goes on to expose the flaws in Rice's original case against him. Following this, Rice receives a distressing phone call from his wife, unveiling that Shelton has sent a copy of the gruesome recording of Darby’s death to their home, causing turmoil for their daughter. Despite Rice’s initial reluctance, District Attorney Jonas Cantrell (Bruce McGill) insists he negotiate with Shelton.
In court, Shelton, representing himself, makes a bold move, temporarily granted bail, where he confronts the judge for enabling criminals' freedom. Soon, he finds himself in contempt of court. He cunningly negotiates a steak lunch in exchange for information regarding Darby's missing lawyer, leading Rice and his team to a horrifying discovery where the lawyer is found buried alive.
The relentless cycle of violence continues when a CIA informant alerts Rice that Shelton has a history of creating inventive means of assassinations. As chaos ensues with multiple deaths, including that of Rice’s assistant Sarah Lowell (Leslie Bibb), the city is placed in lockdown, and Rice is appointed acting District Attorney.
Rice connects the dots and discovers Shelton’s auto garage, which conceals a tunnel leading from the solitary confinement cells, designed to facilitate his escape. Racing against time, Rice anticipates Shelton's next target, city hall, where a bomb is primed to explode.
After evading capture, Shelton, returned to his cell, is confronted by Rice, who finally stands firm against the cycle of revenge. However, in a shocking twist, Shelton’s plan is laid bare as he realizes too late that he inadvertently activated the bomb hidden in his own cell. With a heavy heart, he gazes at his daughter's bracelet, resigned to his fate as the bomb detonates, marking a devastating end to a whirlwind of vengeance and loss.
