The story begins with a narration of the independence of Bangladesh after the 1971 war. Amongst those affected by the partition are two orphans: Bikram Bose (Ranveer Singh) and Bala Bhattacharya (Arjun Kapoor). They meet Lateef (Pankaj Tripathi), who offers them food in exchange for smuggling guns. One of Lateef's customers, an army officer, wants one of the boys as his sex slave; if Lateef refuses, his daughter will be taken. Lateef chooses Bala at first, but Bikram insists that he will go instead. Bala refuses to leave his best friend, and returns to save Bikram from the officer, whom they kill. This makes them partners in crime; when the army chases them, Lateef is killed while trying to protect the duo. Bikram and Bala flee to Calcutta and work at a restaurant. After being mistreated and insulted, they learn that pilfering coal is a way to make easy money.
As adults, Bikram and Bala loot coal trains and sell the pilfered coal; their chief competitor is Dibakar (Deepraj Rana). When Bikram and Bala loot one of Dibakar's trains, his men threaten them. Undeterred, they promise to loot his next train as well. When they arrive to loot Dibakar's train, he calls them "refugees" and a fight ensues. Before they kill Dibakar, Bikram and Bala tell him that they are Indians, not refugees. Now having control of the coal business, they expand into other businesses by laundering money with Kaali Kaka's (Saurabh Shukla) help. They become local heroes by building hospitals, donating to charities and building schools. Although they provide jobs for the poor, their business dealings make them a target of the law. Assistant Commissioner of Police Satyajeet Sarkar (Irrfan Khan) is summoned to arrest Bikram and Bala. Sarkar, knowing that they can cover their tracks with Kaali Kaka, warns them that he will arrest them when he finds evidence against them.
A businessman invites Bikram and Bala to the opening of his new club in Calcutta. He introduces them to Himanshu (Anant Sharma), his assistant. They meet Nandita (Priyanka Chopra), a cabaret dancer. They both fall in love with her, and decide that whoever wins her heart will marry her. Nandita invites them to a theatre to tell them whom she loves. Bala gets into a fight there with a man who insults Nandita and shoots him. Bikram tells Bala to go into hiding, promising not to see Nandita until he returns. Sarkar warns Bikram that if Bala returns to Calcutta, he will be killed. Nandita tells Bikram that she loves him, but if they do not observe Durga Puja together she will never see him again. Bikram agrees to meet her. Later, Bala learns about this through Himanshu, and returns to Calcutta. Enraged when he sees Bikram and Nandita, Bala accuses Bikram of breaking his promise and shoots at him. He hits Nandita instead, who is rushed to hospital and survives.
Bala learns that their businesses are in Bikram's name, and demands his share. Bikram agrees, even sharing the ration card which is proof of their Indian nationality. Bala suggests sharing Nandita; angering Bikram, who fights Bala. Bikram wins but spares Bala as he saved his life. However, he warns Bala that if he bothers Nandita he will kill him. When Bikram proposes to Nandita, she says she cannot marry him unless he leaves his criminal life behind; Bikram agrees. A vengeful Bala blows up Bikram's coal mines and kidnaps Nandita. As Bikram prepares to kill Bala, Sarkar asks Bikram to turn the state's evidence against Bala so he and Nandita can marry. Bala tells Nandita that he will kill her unless she leaves Bikram; Nandita retorts that she loves Bikram. Heartbroken, Bala apologises to Nandita and returns her to Bikram. In reality, Nandita is an undercover police officer helping Sarkar arrest Bikram and Bala. When Bikram prepares to help Sarkar implicate Bala, he encounters the man Bala supposedly killed and learns that he is a police officer. Nandita tries to convince Bikram that he will be treated leniently by the law, he believes the law was responsible for destroying their childhood. Nandita reveals her identity to Bikram, and he realises that she was a trap Sarkar set to separate him from Bala. When she asks him to surrender, he refuses and rejoins Bala.
Himanshu brings Bala into the coal mine to meet Dutta. Himanshu tells him that he is Dibakar's brother, and saw him murdered by Bikram and Bala. He reveals Nandita's identity and tries to kill Bala, but Bikram rescues him and Bala impales Himanshu. While trying to escape, they are then cornered by Sarkar and Nandita, who again tells Bikram that she loves him and he should surrender; Sarkar also tries to convince Bala to surrender. Bikram and Bala see a passing train and run towards it. As Bikram and Bala are inches away from catching the train, Sarkar and Nandita shoot at them. The movie ends with the train passing away without the two implying that they were killed.