Saravanan, affectionately known as Saro, is a carefree and cheerful man who owns a retail cloth store in North Chennai. He crosses paths with Divya, a talented IT employee and the only daughter of the well-respected Tehsildar Anantharaman. Divya dreams of marrying a rebellious partner, yet she has one important prerequisite: he must belong to her Brahmin community. One day, she sees Saro engaged in a spirited brawl with some goons and, mistaking him for a Brahmin because he happens to be sporting a naamam on his forehead that day, she is instantly drawn to him. This attraction leads her to propose a relationship with Saro, and the two soon find themselves happily dating.
However, weeks into their relationship, Divya discovers that Saro is not, in fact, a Brahmin, which prompts her to end their romance. Although Saro is initially furious, he reluctantly agrees to break up, recognizing Divya's firm stance on her cultural values and her desire to marry within her community. Shortly thereafter, Divya's father suffers a heart attack while out walking. Saro happens upon Anantharaman in distress and, acting quickly, takes him to the hospital just in time. This heroic act is eventually revealed to Divya, rekindling her affection for Saro.
Pursuing their relationship further, Saro and his family approach Anantharaman to discuss a marriage proposal. However, the proposal is swiftly declined due to the disparity in their castes. Divya, who holds her father's opinions in high regard, is faced with a conflict between her love for Saro and her father's traditional beliefs. Saro, in a moment of frustration, asserts that every person has a darker side, even her virtuous father, which Divya vehemently denies.
In a state of anger and intoxication, Saro confides in his friends about his resentment and expresses his desire to eliminate what he sees as the root cause of his troubles—Anantharaman. His friends, misinterpreting his frustration, decide to take matters into their own hands. They devise a plan to kidnap and poison Anantharaman while he is out for his morning jog. However, their misguided actions lead to Anantharaman fainting rather than dying.
When Saro learns of his friends' reckless plot, he is furious yet finds himself compelled to cover up their mistake. To protect himself and his friends, he brings Anantharaman's unconscious body back to Divya's home, claiming he passed away from a heart attack. As the family gathers for the cremation, Saro struggles to maintain the facade of innocence. Yet, complications arise when a police inspector grows suspicious and manages to uncover the truth. The investigation intensifies when chaos ensues, and a stray bullet mistakenly hits an ex-MLA nearby, allowing Saro and his friends to escape unscathed.
Upon arriving at Divya's home, Saro's friend reveals that they did not administer poison, but rather anesthetic, which means Anantharaman is still alive. Saro is furious, realizing the predicament he is now in as a result of his friends' blunders. Just then, women claiming to be Anantharaman's wives show up, including a fish vendor and a young woman from North India with an infant. Divya is shaken by the revelations of her father's infidelities. When Anantharaman awakens, he is confronted by the startled women, leading to a humorous and chaotic confrontation.
Seizing this opportunity, Saro explains to Divya that this entire situation serves as a demonstration of his earlier assertion that everyone has a darker side. Ultimately, the trials they endured bring Saro and Divya closer together, allowing them to rekindle their love amidst the chaos of family drama.
