The film opens with Ronnie running towards a corpse and grieving the person’s death before Siya arrives at the spot. A flashback begins.
15 years ago, young Ronnie used to protect his innocent elder brother Vikram from those bothering him. When Vikram got beaten up and troubled by some boys, Ronnie arrived and rescued him by fighting off the boys. His father, Inspector Charan Chaturvedi, didn’t approve of his behavior. One day, Charan went out to rescue people from a riot and ended up getting fatally shot. He made Ronnie promise to be Vikram’s protector forever, which he did. Following their father’s death, Ronnie and Vikram grew up together with their uncle, also a police officer.
Years later, some goons trouble Vikram in a movie theater after he mistakenly spoils their leader’s shirt. Siya, who has just met him, tries to help him but the goons beat him up. Ronnie arrives to help him and sensing threat decides to leave with an apology. However, when he sees blood near Vikram’s ears, Ronnie beats up the goons and is about to nearly kill one of them, before Vikram and their uncle stop him. The uncle offers a police job to the brothers, and Vikram declines. With a number of cases registered against him, Ronnie tells Vikram he can’t join the police force. He convinces Vikram to become a police officer in Agra. Upon joining his duty, he sees the henchmen of a criminal named IPL burn a man to death in front of the police. Vikram is terrified and expresses disgust at the cops’ failure to stop the criminals. He learns an elder cop in their station just thought of bringing those criminals to justice and suffered the consequences by seeing his daughter get killed by one of the criminals.
It is then revealed IPL works for a Syrian terrorist named Abu Jalal Gaza who kidnaps families to use them for terrorism. Soon, the cops find out about the location where IPL’s men have kidnapped families. Since one of them has to necessarily go, Vikram is made the scapegoat but with Ronnie’s assurance, he goes alone at the location. Ronnie meets him secretly, and instructs him to turn lights on and off upon hearing him whistle every single time. Using this technique, Ronnie fights off the henchmen and helps Vikram rescue the kidnapped families. This process is repeated, and Vikram soon becomes a famous cop. Learning that his henchmen are unable to stop Vikram, IPL instructs them to kidnap Ronnie, whom they believe to be an innocent and timid man. They succeed in kidnapping him and ask Vikram to come with the seized commodity and rescue Ronnie. The elder cop tells Vikram to go and save Ronnie, who pretends to be scared and tells Vikram via phone to come in 10 minutes. During that time, IPL instructs his henchmen to chop Ronnie’s thumb if Vikram doesn’t show up, and leaves. However, Ronnie fights them all off and lets Vikram arrest the goon (who killed the elder cop’s daughter). When the goon is being taken to court, Ronnie and Vikram stage a fake arrest sequence in which Ronnie is taken in and cuffed with the goon. During the traffic jam, Ronnie runs with the goon, and Vikram hands over the elder cop a gun to shoot the goon. The goon is killed publicly.
Vikram continues to gain popularity and respect for his sincere behavior. After getting married with Siya’s sister Ruchi, Vikram is told by the government to go for a routine paperwork in Syria. Happily leaving behind Ronnie, Siya and a pregnant Ruchi with a promise to return soon, Vikram goes to Syria and during a video call tells Ronnie someone picked his pocket as he couldn’t be recognized as a cop. When there’s a knock on the door, Vikram goes to attend it and gets brutally beaten up. Seeing this on camera, Ronnie pleads the men to spare Vikram, but they don’t comply. Ronnie vows to rip apart their self-made nation if anything happens to Vikram, and hiding the truth from Ruchi, arrives in Syria with Siya. They try to enlist police help, but to no avail. A Pakistani man named Akhtar Lahori helps the duo track Vikram when Ronnie recalls Vikram’s pocket was picked. Vikram’s wallet is found with a pickpocket, and the cops start chasing after the trio who visit Vikram’s hotel room to find Vikram’s damaged phone. The cops arrive at the hotel to catch the trio, who successfully escape. The trio then starts to search for Vikram with his photos in their hands, and end up finding the attacker. Ronnie beats him up and chases him, exhausting him in the process. Ronnie pleads him to tell Vikram’s location. However, the attacker gets hit by a truck and dies.
The opening scene then plays again, and the story continues from there.
Siya retrieves the attacker’s phone from his corpse and texts IPL to meet him at a hotel, where Abu Jalal Gaza, the attacker’s brother, has also arrived to kill Ronnie (unaware that it’s him). He tells IPL that he has been texted by the killer instead of his brother, and leaves upon seeing the cops arrive. The main cop, however, sides with Ronnie and team, and captures IPL while Jalal escapes in disguise. Feeling IPL might betray him since he has been captured, Jalal orders his men to follow the police vehicle carrying IPL and kill him. Ronnie and team stage a series of events making Jalal’s henchmen believe IPL has switched sides. The henchmen attempt to kill him, and Ronnie rescues him. Feeling betrayed himself, IPL decides to expose Jalal’s plans. It is then revealed that Vikram’s friend Asif and his family have also been kidnapped and kept with him. Asif is made to carry a bomb and explode it in return for his family’s safety. However, Siya arrives and the police frees Asif’s family while she tells him to stop and gets the bomb removed. Ronnie, on the other hand, attacks Jalal’s army in the ensuing prolonged battle. He blows up vehicles, crashes helicopters and battles gunfire with an improvised shield. On the other hand, armed hostages rescued by Ronnie are being taken safely by IPL and Lahori while a girl steps on a landmine. IPL quickly switches positions with the girl, and forces Lahori to leave with the hostages. IPL sacrifices himself when Jalal’s henchmen show up, and he steps off the landmine, killing everyone in the explosion. Ronnie then arrives at the spot where Vikram has been held captive. He fights off some of the henchmen, and Jalal (who met Ronnie at the hotel and promised him to find his brother without knowing him) frees everyone including Vikram, but takes Siya hostage. As Vikram and Siya are caged, Ronnie starts fighting but gets badly hit. While trying to fight back, he sees a sudden transformation in Vikram, who is now enraged to see Ronnie get beaten. Ronnie smiles and stops fighting back, eventually getting stabbed. Vikram escapes from the cage and beats the henchmen to death with a stone, and impales Jalal on steel rods.
Freeing Siya from the cage, Vikram tries to revive Ronnie but nearly fails, with both believing he has succumbed to his wounds. However, as Jalal arrives to attack them, Ronnie suddenly gets up and strangles him to death. Back in India, Vikram is honored for his bravery while Ronnie imagines his father saluting him for keeping his promise and hugging him.