Kanthaswamy, Vikram is an officer with the CBI Economic Offences Wing who, together with a loyal circle of friends, quietly answers the pleas of the needy by writing letters at the Lord Muruga temple and then disguising themselves as an anthropomorphic rooster to become a vigilant force for good.
During a routine CBI raid, he uncovers a stash of black money controlled by Pallur Paramajyothi Ponnusamy Ashish Vidhyarthi, better known as PPP, a haughty and powerful business tycoon, along with his partner Rajmohan Mukesh Tiwari. PPP tries to dodge questions by feigning a stroke, a ruse that infuriates PPP’s daughter Subbulakshmi Shriya Saran, who vows revenge and decides to get close to Kanthaswamy by pretending to fall in love with him.
Kanthaswamy meets her deception with his own counterplay, and what begins as a flirtation quickly evolves into a tense cat-and-mouse game. The two end up falling for each other, even as Subbulakshmi’s motive remains rooted in exposing her father’s wrongdoing. In a separate, lighter thread, Thengakadai Thenappan, also known as Kobarikayala Subbayya Vadivelu, becomes involved in a parallel plot that draws the attention of a local police inspector Mansoor Ali Khan, who is determined to unravel the myth of “Lord Muruga saving the people.”
As twists unfold, the inspector begins to suspect that a larger truth lies behind the apparent benevolence, hinting at the CBI’s secret charitable work, though he cannot confirm it outright. The intrigue deepens when Kanthaswamy discovers PPP’s bank password after cleverly getting Subbulakshmi to reveal critical clues and answer security questions. With the password in hand, he transfers the illicit money into his own account, intending to funnel those funds toward helping the needy rather than funding PPP’s empire.
The revelation that the fortune has vanished hits PPP hard, and he suffers a stroke when confronted with the loss. In a dramatic confrontation, Kanthaswamy unmasked Rajmohan, revealing his true scheming nature and exposing him to the public, which leads to his arrest. Subbulakshmi, recognizing her father’s corruption, chooses love over loyalty to the misdeeds of his world and accepts Kanthaswamy’s proposal; the couple marries and plans to settle in Rajasthan.
Before the curtain falls, Kanthaswamy revisits the ritual of letters tied to a tree—mirroring the ones at the temple—and, with a quiet smile, slips a new letter into a pocket, signaling that his vigilante mission isn’t over and that hope for the needy will continue, in his own distinctive way.
