Prithviraj Sukumaran plays Aadhi, a former drug dealer and enforcer for the Sri Lankan crime lord Damodar. He lives in Detroit, right on the Canada–United States border, and makes a living as a mechanic at a car workshop run by his older cousin, Nandhu as Bhaskar. Bhaskar's son, Mathew Arun as Aju, has a crush on his classmate Deepika, Celine Joseph as Deepika, who is the daughter of corrupt banker Rajan and his wife Seema, Isha Talwar as Seema. Ahmed, an investigation officer and Seema's ex-boyfriend, knows the family dynamics all too well.
Damodar, Rahman as Damodar Ratnam, wants Aadhi back in his fold and tests the loyalty of Aju by sending him to move the latest party drug Redex through Damodar's aide. Aadhi intervenes to protect Aju from trouble, and Bhaskar sends Aju to live with relatives for safety. Deepika, who has fallen for Aadhi, keeps crossing paths with him through Aju, but Aadhi asks her to stay away; she stubbornly presses on and buys a packet of Redex from him. That night, Deepika overdoses and dies, leaving Aadhi overwhelmed with guilt. Seema, shattered by her daughter’s death and by Rajan’s ongoing affairs, decides to leave their home.
On the way to Ahmed's house, Seema is almost assaulted by a group of eve-teasers, but Aadhi steps in to protect her and drops her safely at Ahmed's doorstep. Ahmed's wife is disturbed by Seema’s presence, prompting Seema to leave the house; Aadhi follows and takes Seema to his own place. However, Seema ultimately leaves after learning from Ahmed that Aadhi is part of the gang connected to her daughter’s death.
Damodar lays plans for a major attack during a Detroit festival, aiming to kill three key aides of Antoni, the leader of a rival Polish gang. He orders his brothers Selvam and Bhaskar, along with Aadhi, to carry out the operation. Aadhi is directed to park a car in the lot of a central building where the Polish gang plans to hold an emergency meeting. While parked, he discovers a bomb set to explode within a day. Bhaskar proves unable to complete a killing assigned to him, and Damodar kills Bhaskar in the process.
Enraged, Aadhi eliminates Selvam and confronts Damodar in the same building. A fierce confrontation ensues; though Aadhi is gravely wounded, he overpowers Damodar and stabs him. It’s revealed that Aadhi had informed Antoni about Damodar’s location, and Antoni’s men arrive to finish Damodar off with gunfire. As Aadhi limps away, the bomb detonates, killing everyone inside. He drags himself to Ahmed’s office and collapses. Before arriving, Aadhi had told Seema to visit his house to check the money he had hidden, with instructions to give half to Bhaskar’s wife and keep the other half for herself, and to move to a distant place (Toronto) for a fresh start. In the aftermath, Aadhi briefly regains consciousness.
