Nick Hume, portrayed by Kevin Bacon, is a devoted husband and father of two sons, Brendan and Luke. As a Vice President at an insurance firm, he prides himself on maintaining an orderly life, ensuring everything follows a precise order, just like his balanced accounts. One fateful evening, after a hockey game, Nick and his eldest son Brendan are driving home when they flash their headlights at two cars that pass them by without their lights on. Shortly after, they stop at a gas station to refuel. While Brendan goes inside to get a smoothie, the same two cars they encountered earlier pull in, filled with a gang of street thugs who are about to rob the station.

In a heart-wrenching turn of events, the station owner reaches for his weapon only to be shot dead by one of the gang members. The gang initiates a brutal initiation for their new recruit, Joe, who proves his mettle by brutally slitting Brendan’s throat with a machete. In a desperate struggle, Nick pursues the gang as they flee, tackling Joe in a last-ditch effort to save his son. He manages to pull off Joe’s mask, but the would-be murderer escapes, only to meet a tragic end when a car strikes him on the street. Nick rushes Brendan to the hospital, but the unthinkable happens; Brendan dies in his father’s arms.

Devastated and filled with rage, Nick learns from the District Attorney that due to legal loopholes, Joe will likely face only a light sentence if the case even goes to court. In a moment of defiance, Nick opts not to identify Joe, leading to the case being dropped and Joe walking free. Now a man driven by vengeance, Nick tracks Joe to his hideout and enacts his brutal retribution by killing him in cold blood.

However, the consequences of his actions unravel as Billy, Joe’s older brother and the gang’s ruthless leader, seeks revenge for the death of his sibling. The gang begins a relentless hunt for Nick, culminating in a bold assassination attempt on him in broad daylight outside his office. Nick barely escapes, leaving a trail of violence in his wake and already claiming another gang member’s life in a rooftop standoff.

With his family threatened, Nick comes under police protection, but tragedy strikes again when two officers assigned to safeguard the Hume family are murdered in their watch. The chaos leads to a horrific confrontation where Nick, his wife Helen, and his younger son Luke are shot inside their home, leaving Nick gravely wounded and his family shattered. Awakening in the hospital, Nick learns that his wife has passed and that Luke is clinging to life in a coma.

In a poignant moment, Nick visits his son, grappling with the realization that life does not adhere to the neat equations he once believed in. He tells Detective Wallis, played by Aisha Tyler, “It was never going to balance.” But Nick’s resolve hardens, and he escapes from the hospital, intent on exacting vengeance at all costs.

The following morning, Nick empties his bank accounts and seeks out a connection from one of his co-workers. He tracks down a bar where he applies pressure to obtain information about the gang’s whereabouts, and eventually contacts Bones, a shady mechanic and his personal weapon supplier, portrayed by John Goodman. Bones provides Nick with a cache of firearms but reveals a shocking secret: he is Billy and Joe’s father. Nevertheless, he lets Nick proceed, believing Billy should face his own consequences.

On a mission seemingly destined for self-destruction, Nick shaves his head and dons his deceased son’s leather jacket. Unraveling a trail of bloodshed, he forces a gang member to disclose the rest of the gang’s location before taking out the informant in a chilling display of vengeance. Unfortunately, Billy also learns of Nick’s crusade, leading to more bloodshed and betrayal.

In an explosive showdown at the gang’s headquarters, an abandoned hospital known as “The Office,” Nick methodically takes down several gang members in a spree of retribution. Yet, the confrontation escalates as he faces off against Billy. They exchange fire until they are both left wounded and exhausted, finding themselves in a moment of dark reflection amidst the carnage. Billy chillingly states to Nick, “You look like one of us. Look what I made you.” Unfazed, Nick readies a .357 revolver and questions, “Ready?”

As dawn breaks, Nick emerges from the chaotic scene, dragging himself home in a gang car, bloodied and battered. Upon entering his house, he turns on the TV only to find a video of his family celebrating, reminding him of the happiness that once was. Eventually, police arrive with news of hope: his son Luke has begun to show signs of recovery. In a moment of bittersweet relief, Nick thinks back to the joyous times captured on screen, feeling the weight of his scars and heartache as he succumbs to darkness, juxtaposed against flickers of hope for his surviving son.