The film follows two intertwined love stories set in Chennai and Tiruchirappalli; one unfolds in a single day, while the other stretches across several months.
Amudha, Amudha, a village girl from Tiruchirappalli, comes to Chennai for a job interview with no one to guide her. She enlists the help of a stranger named Jeeva Ravi who agrees to take her as far as the bus stop but ends up riding with her the entire day, waiting through her interview, and dropping her off at her sister’s home in the evening. During that day, she comes to understand him and grows fond of him, while he remains calm and reciprocates her feelings. The next day, Amudha returns to Tiruchirappalli and realizes that she has fallen in love with him, rejecting several marriage proposals that come her way and deciding to return to Chennai to meet him. Meanwhile, Gautham realizes that he has fallen in love with Amudha and resolves to go to Tiruchirappalli to find her, even though he knows nothing about her address beyond her name.
A parallel story follows Kathiresan, Jai Sampath, a reserved metal shop worker, who harbors feelings for his neighbor Manimegalai, Anjali, a nurse who is bold and direct. She takes the lead, testing him with a series of challenges: having him meet her policeman father, confronting a former lover on his own, undergoing an HIV test, and agreeing to organ donation. Through these tests, Kathiresan’s sincerity shines, and the two gradually fall in love, growing closer with their families’ consent. Kathiresan decides to take Manimegalai to meet his family in Arasur, a village near Villupuram, and they board a bus to travel there. Meanwhile, Gautham boards a bus to return from Tiruchirappalli—the same bus that Kathiresan and Manimegalai are traveling on—while Amudha also boards a bus to return from Chennai.
The film briefly shows glimpses of other passengers on the bus journey: a mother and her child, a girls’ athletic team, a newly married couple, two college students who are attracted to each other, and a man returning from Dubai to see his five-year-old daughter for the first time.
Not long after, on the GST road near Viluppuram, the SETC bus is diverted into an oncoming lane because one lane is under construction. A tarp from a truck blows off and blocks the windshield of the other bus, and the driver, unable to see, swerves into the path of the SETC bus. The head-on collision claims about 35 lives instantly, with many more dying on the way to or at the hospital. Gautham finds Amudha severely injured on the other bus, and she is rushed to a hospital. He arrives there with her, only to learn that Kathiresan has died from his injuries. At the hospital, Gautham confesses his love to Amudha at her bedside, and she gradually regains consciousness. Kathiresan’s body is taken away by a grieving Manimegalai and his parents.
The site of the crash is declared an accident-prone area, and the film closes with a clear message about road safety, urging viewers to consider the fragility of life on the road.
