On a busy highway, a lorry careens into a police motorcycle and wrecks a police vehicle. A police officer informs the DCP, Tamizhselvan, Jagapati Babu, who stops the truck by pressing a gun to the driver’s head. He compels the driver to open the back, revealing ₹300 crores in cash. The driver begs for a share, and Tamizhselvan strikes him. The next day, Tamizhselvan addresses the press, claiming that ₹50 crores were recovered and handed to the government, with the driver arrested.
Arjun Ramakrishnan, Vishal Krishna, arrives in Chennai to win the heart of Divya, Tamannaah Bhatia, a psychology student. With a little help from a local, bumbling don named Deva, Soori, he manages to win her over. Divya’s elder brother is Tamizhselvan, an honest and steadfast DCP in the city, and the wedding is soon set.
When goons kidnap Tamizhselvan in retaliation for foiling a black money scam six months earlier, Arjun rescues him and reveals a startling truth: he is a CBI officer who has uncovered ₹250 crores of black money hidden in Tamizhselvan’s home. In a prior raid during the black money operation, ₹300 crores were seized, but Tamizhselvan publicly claimed they had recovered only ₹50 crores. Arjun seizes the money and, instead of arresting Tamizhselvan to protect his public image, decides to pursue the larger goal from the shadows.
The driver who helped unleash the sting is released and visits Tamizhselvan’s house, where he reveals a twist: Arjun is not a genuine CBI agent but a recently released prisoner playing a mission to recover more black money. In the ensuing pursuit, Tamizhselvan fires on Arjun’s SUV, sending it crashing and leaving Arjun unconscious. He awakens in a hospital with seeming memory loss, and Tamizhselvan keeps him under custody in a house, where a psychiatrist named Dr Boothri, Vadivelu, is brought in to restore Arjun’s memory so he can reveal where the money is hidden. Unknown to all, Arjun is not truly memory-impaired.
That night, he sneaks out and steals the black money of a Union Minister, converting it to white with the help of a hawala trader. Tamizhselvan and the Union Minister soon realize Arjun’s ruse: he has not lost his memory, and he has taken even more money.
Past: Arjun hails from Manimangalam, a remote village starved of basic amenities—roads, water, schooling, and proper housing. When the village’s only primary school collapses, he confronts the corrupt MLA Sivagnanam, who pockets the funds meant for development. Sivagnanam dismisses him and defends his corruption, even as the local Union Minister proves just as corrupt. After two friends are killed by Sivagnanam’s men, Arjun resolves to reclaim the black money amassed by Sivagnanam and the Union Minister to rebuild Manimangalam.
Present: Arjun brings Tamizhselvan, the Union Minister, and Divya to Manimangalam and reveals that he used the money hoarded by the Union Minister along with Sivagnanam’s ₹300 crores to renovate the town, giving due credit to the Union Minister. The villagers’ newfound regard for the minister prompts Tamizhselvan to drop charges and arrest him, while it becomes clear that Divya, Tamizhselvan, and Arjun have all played active roles in transforming Manimangalam. The story closes on a note that progress and justice can emerge when power is redirected toward the betterment of a community.
