The entire film is presented as a flashback by Sub-Inspector Ashwin Gupte (Tusshar Kapoor).
The Maharashtra police seizes large quantity of arms from the house of Dr. Iqbal Ansari (Atul Kulkarni), a physician from the riot-torn region of Chandangarh. The officials conclude that he is an agent of Pakistan intelligence agency collaborating with terrorists. Ansari is arrested as per Prevention of Terrorism Act, 2002 and will be presented before a special court in Mumbai. But, the convoy of police vehicles bringing Ansari from Chandangarh is ambushed by an unknown group. The police somehow manages to save the accused’s life, but suffer heavy casualties. The group, led by Yashwant Angre (Ajay Devgan), a ruthless killer and former police officer, seems determined to free Dr. Iqbal Ansari from the government’s custody.
Minister Deodhar (Sabyasachi Chakrabarty), a high-ranking politician in Maharashtra who represents Chandangarh, accuses Pakistan of “proxy-war” against India through the communal riots and the ambush on police forces. The police chief decides to send a team of five police officers to bring the accused to Mumbai so that he may appear in court for the hearing. The leader of the team, Deputy Commissioner of Police Anant Shrivastav (Amitabh Bachchan), is a policeman on the verge of retiring from his failing career, possibly because he never succumbed to corruption and other personal interests. He accepts the mission, thinking that he will finally be recognized and finish his career by being promoted to Additional Commissioner of Police. DCP Shrivastav’s team consists of Senior Inspector Shekhar Verma (Akshay Kumar), a corrupt, morally bankrupt cop, rookie Sub-Inspector Ashwin Gupte (Tusshar Kapoor) and two constables, Kamlesh Sawant and Gajanan Mhatre. A woman named Mahalakshmi (Aishwarya Rai) joins them for her protection, as she is the only witness to have seen Yashwant Angre.
The team is armed with traditional Indian police weapons and ready to go, but danger lurks everywhere as the gang is determined to make sure the police team and Iqbal Ansari does not make it to Mumbai. The mission turns into a battle for survival when the team is attacked at various points during the journey through arid landscapes and tiny villages of rural Maharashtra. When the team reaches an abandoned cottage in a forest en route, there is another shoot-out with gang members and the team finds itself heavily outnumbered. Against DCP Anant Shrivastav and Inspector Ashwin Gupte’s judgment, Senior Inspector Shekhar Verma tries to force an exchange of Dr. Iqbal Ansari in return for their lives. At this point, Dr. Ansari breaks down and reveals that the gang is not planning on freeing him, but instead on killing him after their use. He goes on to reveal that he knows the whereabouts of a certain file which will reveal the true face of Minister Deodhar. The file with Dr. Iqbal Ansari’s testimony could bring the politician to court who built his career on inciting Hindu-Muslim religious antagonisms. So, it is Minister Deodhar who is using the gang under Yashwant Angre to obtain the file. Dr. Ansari was framed as an “Islamic terrorist” when he threatened to expose the file. At this point, Senior Inspector Shekhar Verma’s intentions change dramatically and he plans an escape from the cottage. The plan is successful and they manage to get out and get Ansari, who is fatally injured in the encounter with the gang, to a nearby hospital in the fictitious city of Nairoli. DCP Shrivastav figures out that AdCP Naidu (Prakash Raj), who is DCP Anant Shrivastav’s senior, was the mole leaking the information about their whereabouts to the gang.
At this point, Minister Deodhar, the politician using the organization lead by Yashwant Angre, and ACP Naidu come up with a plan to turn citizens against the police team by declaring in a press conference that the police team has gone “rogue” and is now protecting Dr. Iqbal Ansari on the directions of Pakistan’s Inter-Services Intelligence. Seeing the news on television, several locals gather at the hospital and threaten to barge inside. DCP Anant Shrivastav confronts them and urges them to have faith in his team, and not go by what they hear in media.
The police team then commissions a train to take them from Nairoli Railway Station to Mumbai. However, once again the gang arrives at the station and there is another shoot-out. The cops manage to get Ansari on board the train, but Constable Kamlesh Sawant dies trying to divert the attention of the gunmen. After reaching Mumbai, Dr. Iqbal Ansari is again taken to a hospital, where he is declared dead. This is a severe jolt to the efforts and reputation of DCP Shrivastav’s team.
However, the team manage to unearth another piece of evidence against Minister Deodhar and AdCP Naidu; the old file containing incriminating details against them, hidden away by a now-killed journalist in a locker in Mumbai’s General Post Office. Senior Inspector Shekhar Verma and Mahalakshmi (who is now his girlfriend) manage to find the file, but Yashwant Angre confronts them as they attempt to leave. Shekhar Verma gives the file to Mahalakshmi and asks her to take it to DCP Anant Shrivastav, and engages Yashwant Angre and his men to allow her to escape. At this point, it is revealed that Mahalakshmi is actually an agent of Yashwant Angre, her mission being to leak the whereabouts of the file to the police team and collect information on their plans to retrieve it. Mahalakshmi kills Shekhar Verma, who believed she was in love with him— but not before exposing Mahalakshmi’s reality to DCP Shrivastav, unbeknownst to her and Yashwant Angre. DCP Shrivastav and his team hunt down Angre by following Mahalakshmi, and capture him after a fight. Mahalakshmi is killed during the encounter, when Angre uses her as a protective shield against the gunfire. The police are also able to retrieve the file indicting Deodhar.
Armed with compelling evidence from the file, the court is able to convict Yashwant Angre, Minister Deodhar, and ACP Naidu. On the way to prison in a police van, Angre sees that the bolts holding his handcuffs are actually loose. Breaking free, he grabs a rifle and attacks the constables in the van. Sub-Inspector Ashwin jumps out of the van to find Angre holding a constable hostage. Angre goes to shoot Ashwin and the constable, but only then he notices that the gun has no bullets and surrenders to the cops. Ashwin then takes out his pistol and shoots Angre twice, and shows him the screws of the bolts, indicating that they were purposely removed. He then shoots Angre with his gun. The film ends with Sub-Inspector Ashwin ringing the department and informing them that a convict was killed in an encounter while trying to fire at the policemen in an attempt to escape from custody.