Vikram (Jayam Ravi) is an honest cop who serves as the Assistant Commissioner of Police (ACP) in Chennai. He has a team of police officers, namely, Sathya (Varun), Akshara (Akshara Gowda), and Prasad (Nagendra Prasad). He lives with his parents, elder sister (Sindhu Shyam), and brother-in-law (Prakash Rajan). His family sets up an arranged marriage for him with Mahalakshmi (Hansika).

Vikram is tasked with tracking Aadhithya Maravarman (Arvind Swami), a monarch's son and a crooked thief, who mysteriously became rich by robbing jewels and money. He is also involved in drug trading and pumping business. Aadhithya uses an ancient manuscript, which enables him to access Astral Projection by looking straight at their eyes. While interrogating Aadhithya after catching him , Prasad is killed by Sathya, (whose body is occupied by Aadhithya). When Vikram goes to shoot Aadhithya out of anger, Aadhithya enters Vikram's body and begins impersonating him, while Vikram is unconscious. Aadithya, now in Vikram's body, masks the killing of Vikram's best friend by saying that Sathya and Prasad had personal vengeance. After coming to Vikram's home, Aadhithya comes across Maha. He lusts for her and even pinches her belly in the car, but forgets about her eventually to focus on his revenge on Vikram. Meanwhile, Vikram, who now is trapped in Aadithya's body, is surprised to find himself imprisoned, and gets a visit from Aadithya, who tells him about his plan to make Vikram lose his job and free himself. Afterwards, Vikram manages to convince Sathya that he is not Adithya and escapes from prison. After escaping from the prison, Vikram calls the Chennai City Police Commissioner Rajkumar (Ponvannan) and tells the mishaps of events which occurred. Aadhithya overhears their conversation and kills the superintendent. Aadhitya later kills Akshara when she is informed by Satya. Aadhithya also reveals that he has a confession video which says that Vikram blamed Aadhithya for his father's mistake.

At the same time, Aadhithya unlocks Vikram's police data and takes the video evidence of his father, who Aadithya had impersonated , robbing the bank and threatens to reveal it to the public, but Vikram contacts Professor Chezhiyan (Nassar), Aadhithya's head in archaeology where he gets the manuscript which gives him his power. Chezhiyan thinks that he is being cheated and goes to Aadhithya, but Aadhithya reveals himself to be in Vikram's body, and makes Chezhiyan his bait to catch Vikram while in the complex where Vikram was supposed to meet Chezhiyan. When Aadhithya tracks Chezhiyan, Vikram hides and talks to Chezhiyan, who says that Aadhithya's power is only in his body (in which Vikram is) and in other bodies, his power does not work, so Vikram uses Chezhiyan to take the manuscript from the commissioner's office. Aadhithya later kills Chezhiyan.

Vikram puts a bomb on himself so that Aadhithya may get scared that if his body goes away, he will not be able to use his powers. Vikram and Aadhithya switch over to their original bodies after Vikram threatens to harm Aadithya's body, and Aadhithya pleads with Vikram to diffuse his bomb. Vikram, who had double-crossed Aadhithya, knocks him out, and while taking him to arrest, Aadhithya switches his soul to Vikram's father Arumugam (Aadukalam Naren) and beats Vikram. He then switches to Maha's body, stabs him, and threatens to kill Mahalakshmi if he does not remove his bomb. Vikram defuses the bomb. As Vikram had double-crossed and betrayed him, Aadhithya drives off with the unconscious Mahalakshmi. Vikram chases them and ends up in the coast. A weakened Vikram fights Aadhithya. Aadhithya quickly but brutally beats up Vikram. But Vikram snaps back and fights Aadhithya. Vikram fractured Aadhithya's neck and left hand and returns home with Maha.

In the end, to everyone's horror, Aadhithya survives and glares into the screen, which goes off with the title "Bogan 2 will continue".