Jayam Ravi, Aravind Swamy, Nayantara
The film opens with a scene of a low-level party cadre Senkalvarayan (Thambi Ramaiah) tying a flag to a street-lamp post. Suddenly his pregnant wife gets labor pain but he completely ignores it as he is more dedicated to his leader and party than family. At the same time, the party leader (Nassar) happens to visit the locality; upon hearing his party cadre's ignorance to pregnant wife, the party leader lends his car and orders his driver to immediately take the pregnant lady to the hospital and she delivers a baby boy Pazhani /Siddharth Abhimanyu(Arvind Swamy) before they get to the hospital. When Pazhani is fifteen years old, he secures first rank in his 10th standard state exam and visits the party leader for his blessings with his father. While they are waiting in the party office for the leader to come in, they witness a murder of a rebel party candidate by their own revered leader due to caste related comments by the rebel on him. When the leader asks Senkalvarayan to take the blame by saying that he killed the man due to rage on the rebel's comments, Pazhani volunteers to take the blame and willing to go to jail citing leniency of juvenile laws in exchange for an MLA seat for his father.
15 years later, a trainee IPS officer Mithiran (Jayam Ravi) and his friends (Ganesh Venkatraman),(Harish Uthaman),(Rahul Madhav), (Sricharan) discreetly assists the police in catching a gang which kidnapped four girls. One day Mithran and his friends receives a cryptic text message on his phone from an anonymous number stating that he/she is aware of their discreet activities. In the evening, they go out to meet that person who turns out to be Mahima (Nayantara) who loves Mithran. Flashback shows how Mahima fell in love with Mithran at their first meeting. Later that same night they happen to witness murder of a man named Raman who is a social activist with the pretence of snatch theft. Mithran and his friend catch the gang and their leader and hand them over to the police however four days later the leader of the gang comes to the IPS headquarters with the home minister. This political and organized crime comes as a shock to Mithran's and his friends. Mithran takes them to his house and shows his research on connecting all small unrelated incidents into the global view of a hidden network of politicians, industrialists and criminals who bend the law for their own financial benefits. He singles out three prominent business oligarchs (a pharmaceutical mogul, a mineral magnet, and a don). Then when he tries following one he comes to know that all three are a group and controlled by Siddharth, a scientist.
Siddarth uses the medical field for the wrong reasons and his own profit. At that time a Swiss pharmaceutical company owner Angelina and an activist tries to make generic medicines for life-threatening diseases available in India at low cost affordable by poor people. Siddharth kills her before she signs the agreement document with the government and Mithran is also shot at the same time. While he was recovering from the gunshot wound in the hospital, an electronic bug (GPS + audio transmitter) is implanted during surgery. Through the bug Siddharth listens all of Mithran's plans and continuously monitors his whereabouts and whatever he talks via audio transmission. Then comes a evidence against Siddharth in the form of Ms. Manimekalai (Abhinaya). She was a scientist at Siddharth's research Lab, where a sea weed that can cure diabetes is found abundantly in the oceans. Siddharth tries to sell the technology and rights to extract medicine from the sea weed to multi-national pharmaceutical companies that was opposed by Ms. Manimekalai. So Siddharth has her raped and killed by his goons. But before being killed she records a video and puts it on a SD card so that someone will find it. But before Mithran can find the SD card, Siddharth finds out and assigns Vicky (Vamsi Krishna) to recover the SD card but Mithran tells his friend to get the SD card. He successfully got the SD card after the fight with Vicky but through the bug Siddharth knows this and kills Jana (one of Mithran's friends).Finally Mithran finds out that there is a bug inside him and takes it out. He then uses it to his advantage to expose all of Siddharth's wrongdoings.
When Siddharth is arrested Mithran tells him that the medicine was patented in Manimekalai's name even though Siddarth was the inventor and will be made as generic medicine instead of a patent-protected one. Mithran makes a deal that he would save Siddharth's life for information and evidence on all of his criminal associates and activities and gives him a bullet proof vest to fake his death during his transport to court.But to Mithran's surprise he doesn't wear the vest but tells that he hid all the evidence in a SD card in the bullet proof vest. Siddarth is fatally shot by his girl friend Shilpa as an act of vengeance for killing her father.