Raghuvaran is a graduate in Civil Engineering, but has been unemployed for four years. He is adamant about working in a job related to his field only and is unwilling to accept any other profession. He often comes into conflict with his father, who considers him irresponsible. His younger brother, Karthik, works in an IT company, earning well and, evidently, his father's approval. Raghuvaran's mother, Bhuvana, however, supports him. Raghuvaran falls for his neighbour's daughter, Shalini who hates him initially, but warms up to him after hearing about the difficulties he is facing and eventually reciprocates his love.

One day, while Raghuvaran's father and Karthik are absent, he is asked to look after his mother, who has a heart condition. However, he goes out on a date with Shalini. He gets continuous phone calls from his mother, which he ignores despite Shalini's insistence to pick them up. However, on returning home, he finds out that his mother had died of a heart attack. Raghuvaran feels guilty about not being there when his mother needed him and develops depression. Meanwhile, Bhuvana's lungs are transplanted into Anitha, a chain smoker who developed lung cancer. Anitha's father Ramkumar is the chairman of a civil engineering company in Chennai and offers Raghuvaran a job as a token of his gratitude for saving his daughter's life. Raghuvaran accepts the job while also requesting Anitha not to smoke, which she agrees. Six months later, Raghuvaran is offered an assignment on a government project to construct high-rise flats to re-house people living in a nearby slum. Azhagusundaram and Manickam are appointed as his assistants. He successfully wins the contract from the government and begins work on it immediately.

Arun Subramaniam, a business novice who took over his father's company's Chennai branch, bids for the same contract, even by using illegal methods. Furious that he did not get the land, he tries to thwart Raghuvaran's progress in a number of ways. Raghuvaran overcomes each of these obstacles and continues his work, but Arun eventually hires rowdies to beat up Raghuvaran's workers at the construction site. The workers get injured and end up in hospital, which prompts Raghuvaran to go to Arun's office to put an end to this issue. He makes Arun confess that he sent the rowdies, which is recorded by a micro spy camera, and demands an apology from Arun, blackmailing him that otherwise the video would be made public. Fearing that the video could tarnish his reputation, Arun's father, Venkat, sends his son to the hospital to apologise. Raghuvaran accepts the apology and the project is completed within ten months.

On the day of the flats' inauguration, Arun and a gang of rowdies ambush Raghuvaran en route. He outwits them but spares Arun, much to Arun's surprise. Raghuvaran says he has no intention to compete with or beat him and wishes to be his friend. Raghuvaran takes Arun to the site on his moped, where the state public works minister and Anitha inaugurate the flats.