In Afghanistan, a drone flies over a small village and gets the attention of the locals, who immediately get ready for an attack. Soon a bunch of American soldiers arrive and find the town empty because everyone is hiding inside. The team keeps moving and when they find a suspicious man with a bomb, they immediately surround him, threatening to shoot him if he doesn’t drop his weapon.
At first the man tries to ignore the threat, but when he sees the soldiers mean it, he takes out a gun which forces the soldiers to instantly kill him with a few shots. Then Jake informs Colonel Mason about the dead man and the bomb, asking for permission to disarm it. Mason refuses, but Jake ignores him and works on it anyway, successfully disarming it.
At that moment, a secret second bomb goes off and kills most of the soldiers. Soon the men come out of the buildings and surround the Americans as they open fire and a vicious gunfight begins. American soldiers are falling everywhere and only Jake and Mason are left alive.
Jake runs to join his colonel and is almost shot by the enemy, but Mason saves his life right before a helicopter shows up. Five years later, Jake is trying his best to deal with a new life as a civilian while taking medicine for his PTSD. His new job is at an auto shop owned by Earl, where he has to work extra hard to deal with some entitled clients.
After work, Jake goes home to spend his time with his family. He always makes sure to keep a happy mood for his son, but in private, things get tense when his wife points out they have lots of unpaid bills. However Jake promises to take care of it like he always does.
When Jake puts his son to bed, he shares a picture and a story about his old squad and the fact Mason was at the hospital when the baby was born. Jake laments not having spoken to Mason in a while, and when the kid asks if he ever killed anybody, Jake dodges the question. The next day, Jake goes to work and finds a group of gangsters claiming that Earl owes them money.
When Jake tries to kick them out, the leader Fresh sends his men to beat him up, but Jake easily defeats them all with a wrench. Fresh makes him stop by showing him his gun, then he leaves with his gang after promising a round two in the future. Afterward, Jake confronts Earl, who confesses he used to be part of a gang too but was fortunate enough to leave that life and build something he could call a home.
Earl promises he’ll always protect his block, so Jake doesn’t need to worry about his family. Jake feels like he’s still at war and calls his family to check on them, hearing his wife say he should’ve called the cops instead of getting involved. Later in the evening, Jake goes home and sees Fresh in his car mentioning payback before driving away.
A panicking Jake rushes inside the house and is devastated to discover his family is dead, so he screams and cries as he has a total breakdown. Moments later, the police arrive and try to ask him some questions, but Jake snaps and goes away in his truck. He drives through the city looking for Fresh’s car while his mind keeps going through his happiest family memories.
Eventually he finds the car outside a naughty club, so Jake rushes inside with a gun in hand and begins shooting every single gang member without hesitation. When he is about to kill Fresh, the man explains that he hadn’t meant to kill Jake’s family but he was given no choice. This doesn’t change Jake’s mind and Fresh gets shot too.
Five months later, Jake is serving time in prison for his crime and his PTSD gets worse as he spends most of his day picturing Fresh killing his family. One day, Jake is surprised to get a visit from Mason, who offers his help to reopen the case. However Jake refuses because he thinks he belongs there and repeats what he told the judge: he got his revenge and now has zero remorse, he’d even do it again.
Then Jake asks Mason to never come back and tells the guard to take him back to his cell. That night, Jake keeps remembering his days with the army and how Mason had retired after saving his life. Sometime later, Jake is visited by a stranger named Ramsey, who mentions he runs a private task force.
However Jake doesn’t let him say more and once again asks the guard to take him back. Later in the evening, Jake is dreaming about his family when suddenly, a bunch of masked men break into his cell and sedate him before kidnapping him. When Jake wakes up later, he finds himself out of prison and discovers his kidnapper is Ramsey, who confesses he's been watching Jake for a long time and is impressed by his record.
Ramsey’s organization, called Section 8, doesn’t play by the rules, and Ramsey thinks they can give Jake back his purpose. As a final touch, Ramsey says Jake’s son would like to see him as a hero, not a convict, so Jake finally accepts to join. Later in Washington DC, Ramsey introduces Jake to the rest of the team: Elias, Ajax, Brunner, and Mueller.
Then he gives him a tour of what he calls the Batcave while explaining that they have eight operatives in Washington and eight elsewhere in the world. Their orders come from the State Department and the NSA, always related to taking care of threats against national security. Since Jake is just starting, Mueller will be his watcher and go with him to all missions until he gains seniority.
Jake will also be given a bank account, an apartment in the city, a vehicle, a backstory, and an alias because to the world he’s dead. Then Ramsey has to leave, so it’s up to the team to put Jake through the initiation process. Ajax starts to provoke him, pushing him around and throwing some punches.
Jake refuses to fight and does his best to dodge them all, but Ajax becomes so aggressive that he makes Jake snap. He pushes Ajax to the floor and almost stabs him in the eye with a pen, but suddenly a memory of his family flashes in his mind and he calms down. Then Jake leaves, and a frustrated Ajax points out that Jake has shown fear and that means he doesn’t belong with them, but Mueller disagrees.
Sometime later, Jake and Mueller get on a plane and discuss Jake’s first mission. The target is a man called Castillo, a defense contractor that also works as a weapon dealer. Recently he's put his hands on some dangerous schematics that he'll sell to the Russians, so Jake’s job is to retrieve the schematics and kill Castillo and his men.
Jake realizes they’re essentially a group of assassins and doesn’t look forward to killing again. In the evening, the duo makes it to Mexico, where they find Castillo about to make the exchange with a Russian negotiator in a warehouse. While Castillo and the Russian argue, Jake sneaks around and discreetly kills a guard.
The noise makes both gangs think the other is setting them up and this turns them against each other, so their argument soon escalates into a full gunfight. The gang members begin dying one by one and even make a car explode which causes the fight to finally stop. Then Jake comes out and kills every survivor before looking inside the car, where there are two very scared women.
Jake ignores them and takes the schematics before leaving. Later at the base, Ramsey scolds Jake for compromising the integrity of their mission by leaving those two women alive. Jake tries to explain they were victims and accuses Ramsey of disregarding human life, so Ramsey threatens to send him back to prison if he doesn't obey.
Then Jake is dismissed, and Mueller tells Ramsey that Jake did good, but Ramsey is still hesitant, so Ajax cuts in and implies that Ramsey made a mistake. Once he’s left alone, Ramsey calls someone named Locke. The next day in Nevada, mercenary Locke breaks into a hotel and kills a few employees before entering a room, where he scares away the women before confronting his victim.
The guy knows Ramsey sent Locke and tries to bribe him with a huge amount of money, but Locke kills him anyway. Afterward Locke escapes through the hotel’s casino, but the guards immediately get suspicious and go after him. Locke easily beats up every guard that comes close and begins running, breaking things on the way and knocking out the guards that keep coming.
Eventually he takes out his gun and shoots a few bullets just to cause panic in the gambling crowd, he also kills a guard before going outside and stealing a car to escape. Meanwhile Jake moves into the new house and is shocked to find a frame with a bunch of pictures from his time in Afghanistan. This reminds him of a conversation he had with Mason, during which Jake blamed himself for getting him injured and Mason made sure to comfort him.
Later, Jake is drinking at the pub and Mueller joins him, so Jake tries to get some information out of her. Mueller doesn’t know anything about Ramsey, but she explains that she used to be in the army and punched a commander officer that reprimanded her. Sometime later, Ramsey gives them their new mission: they must retrieve dome digital information about a sensitive case and kill Senator Graham, who is a traitor to the country and has paid many people to stay free.
Security will be very strict, so Ramsey reminds everyone, especially Jake, that they must fight back. A few hours later the group makes it to Graham’s event in California disguised as landscapers. Mueller sneaks inside to kill all the guards she can find and eventually security learns of the situation so they take Graham away in a van.
While Mueller hacks the senator’s computer, Jake chases after Graham, shooting a few bullets to no avail. The van is too fast for him, so Jake takes a shortcut by jumping over a hill and manages to block the road. A guard tries to fight him but Jake quickly kills him before approaching Graham, who begs for his life while saying he has a family.
Jake is suddenly overwhelmed with memories and decides to let Graham live. However the team shows up and Ajax kills Graham before reminding Jake not to hesitate. Later at home, Jake struggles with his guilt and cries while looking at pictures and drinking.
Suddenly he sees masked men running outside his window, so he hides before they enter his home. The men look for him in every room, but Jake manages to escape through the back door. The next day, Jake goes to see Mason and tells him the whole story.
Mason mentions he knew the real Section Eight was dismantled in the 90s and the one functioning now is just a cesspool of disgraced agents from the army, CIA, FBI, and the like. They even have important connections in Washington, so if Jake is running from Section Eight, he’s in serious danger. Mason has never heard of Ramsey and promises to make some calls, he also agrees to help Jake with some money and a gun.
Afterward Jake returns to his hometown and gets a call from Ramsey, who wants to meet to talk things out but Jake refuses. Then Ramsey asks Mueller to call Locke, who is currently hiding in Argentina, to give him the mission of killing Jake. Sometime later, Jake bumps into his son's best friend and as they talk about the tragedy, he learns that before his family's murder, Fresh was seen with people in black suits like the secret agents seen in comics.
Before he can get any more information, Locke shows up and opens fire, so Jake pushes the kid into a shop before running away. Panic takes over the area as Locke kills a few civilians, and soon the police arrive only for Locke to shoot them as well. This distraction allows Jake to escape, so Locke steals a police car and goes looking for him while calling Ramsey to tell him what happened.
In the evening, Jake is hiding at Earl’s shop and remembering how Earl raised him after his parents died. Suddenly the computer starts beeping to announce the arrival of the team, so Jake and Earl grab some weapons to fight them. Jake almost gets shot by Elias, but Earl quickly takes him out.
Next Brunner jumps on Jake and they begin fighting on top of a car when suddenly, Ajax shoots at them. Brunner turns around to yell at his carelessness, and Jake uses the chance to stab him with a screwdriver. When Ajax opens fire again, Jake uses the body as a shield and retrieves his gun to start shooting back, but he soon runs out of bullets.
Ajax has a few left but wastes them on purpose because he wants to fight Jake hand-to-hand again to prove he’s better. The men begin exchanging hits all over the shop and Ajax tries to stab Jake, but he ends up getting shot by Mueller. Afterward Jake checks on Earl, who is fine and gives Jake his car keys so he can escape because the cops are coming.
Later in the car, Mueller says she saved Jake because she also wants to leave Section 8. Jake doesn’t think he can trust her and demands to be taken to wherever Ramsey’s staying. The next day the duo arrives in Montana and tries to sneak through a forest to find Ramsey’s cabin, but when Jake turns around, he’s suddenly knocked out.
After dreaming of his family again, Jake wakes up tied to a chair in a room with Ramsey and Mueller, who has been working for Ramsey to set up this trap for Jake. Ramsey says he has a surprise and Jake is shocked to see Mason enter the room, learning he’s been working with Ramsey as well. The organization had been needing an agent with Jake’s skills so Mason told them how to get to him, this means they were the ones to pay Fresh to kill his family.
Jake can’t believe Mason betrayed him, but Mason just says that Jake was wasting his talent on cars and a kid. Afterward the group leaves Jake alone and Mason pays Ramsey and Mueller the money they agreed on. Ramsey says they should kill Jake because he’s a liability and Mason agrees, but he looks inside.
While Mueller counts the money, Mason goes to see Jake and frees him before confessing the truth: he had been hired to take down Section 8 from the inside, and now he wants Jake to help him finish the job. Then Mason sets off the alarm on purpose, and when two guards come to check, they quickly kill them. More men keep coming and the duo shoots them all as they make their to find Ramsey.
Another gunfight begins as bullets destroy their surroundings, and when Ramsey sees them, he hides with Mueller and offers Jake the money from Mason. Jake refuses with a shot, so next Ramsey tries to convince Jake that this is all Mason’s fault but Jake doesn’t believe him. While they argue, Mueller sneaks around and tries to shoot Jake, but Mason tells him to move and takes the bullet instead, knocking Mueller down in return.
Jake rushes to check on his friend and Ramsey tries to grab the money, but Jake scares him off with a few shots. Then Mason asks Jake to finish the job and dies. At that moment Mueller cuts in and tries to shoot Jake, but she’s out of ammo so they start fighting hand-to-hand instead.
After exchanging a few hits, Mason stabs Jake in the shoulder, but he uses the chance to turn her own hand against her and kill her. Afterward Jake goes outside and sees Ramsey flee in a car, so he steals a vehicle and goes after him. Both men open fire as they drive like crazy, and Ramsey gets so distracted that he ends up crashing.
Jake walks over to the wreck, and when Ramsey insults him for hesitating, Jake finally kills him. In the evening, the police bring Jake to meet General Savoy, who Mason was working for. Savoy offers Jake a job and a clean slate if he accepts to join his team, but Jake declines the offer saying that he has nothing to fight for.
Just in case, Savoy gives him his card anyway. Later Jake returns home only to find Locke waiting for him because he still wants to finish his job as his reputation demands. Soon a hand-to-hand fight begins and both men show their amazing fighting skills while using any object or furniture in the room to attack as well.
When the fight moves to the kitchen, both of them grab a knife and keep hitting each other until Locke throws Jake on the floor. This allows Jake to retrieve his gun and finally kill Locke. The next morning Jake sends a voice message to Earl, thanking him for everything and announcing he’s leaving.
Meanwhile Jake is taking a bus and sees a mother having a sweet moment with her son. Memories of his own family flood his mind again and Jake calls Savoy to accept his offer, saying he does have something he wants to fight for. Savoy immediately welcomes him to Section 9.