Misha (Yami Gautam) and her son Robin become the victims of a bank robbery getaway during a shopping trip. Liak (Nawazuddin Siddiqui) and his friend Harman (Vinay Pathak) rob a bank and use Misha’s car to flee. Robin falls out of the moving vehicle during the struggle, and Misha is shot by Liak. Harman jumps out of the car to protect the money while Liak is arrested. Both mother and son die from their injuries in the hospital.
Raghu (Varun Dhawan), shattered from the loss of both his wife and son, immerses himself in seeking revenge on both culprits. Liak is sentenced to 20 years in prison, but refuses to reveal the identity of his partner in crime. Raghu learns about Jhimli (Huma Qureshi), a prostitute who is Liak’s girlfriend, and visits her to inquire about the missing partner. After Liak’s sentence, Raghu exiles himself to a reclusive life at a train station he gets off at – Badlapur.
15 years later, a terminally-ill Liak is paroled from prison on compassionate grounds. Unknown to Liak, Raghu has facilitated the release by providing a letter of pardon for Liak to the court, in exchange for being told the partner’s name by Liak’s mother. Bent on vengeance, Raghu finds Harman, who now runs a well-established restaurant. Liak is kept under watch by police as they believe he will lead them to the unknown partner. Liak contacts Harman, and arranges to take his share of the money. However, Raghu has already interrogated Harman and Harman’s wife Kanchan (Radhika Apte). Harman tells Raghu that it was Liak and not him who killed his son and wife. Raghu is not convinced and takes Liak’s share of the money, killing both Harman and his wife.