- Directors: Sundar C
- Producers: K Muralitharan, V Swaminathan, G Venugopal
- Writers: Kamal Haasan, Madhan
- Genres: Drama, Comedy
- Actors: Kamal Haasan, R Madhavan, Kiran Rathod, Nasser, Santhana Bharathi
The film begins with ad film-maker Anbarasu (R. Madhavan)- who prefers that his name is mentioned in the abbreviation of A. Ars rather than his full name, arriving at the Bhubaneswar airport in Orissa, India. He is about to board a flight back to Chennai for his own wedding. However, he learns at the airport that his flight is cancelled due to the bad weather in the state where heavy floods and torrential rain due to the wet season have affected air traffic. While waiting for further announcements, Ars watches a television news of a terrorist threat at an airport in Mumbai, making him suspicious when he sees a limping man carrying an old sack on his hands. He informs the authorities, who find out that the man only has a cucumber in that bag and nothing else.
The man, a physically disabled man named Nallasivam (Kamal Hassan) introduces himself to Ars and both of them get to know each other. However, Ars underestimates Nallasivam, ignoring his advise and friendly acquitance, resulting in some comical events in the airport itself. Announcements are finally made that the flights would not board on that day and Ars will have to reserve place in nearby hotels to put up the night. Ars realizes that the five star hotel that he was staying in before is now fully booked, leaving him optionless. Nallasivam however helps him find a place in a two star hotel nearby, in which both Nalla and Ars have to share the same room. Ars’ resentment of Nalla makes him act selfishly in trying to get rid of Nalla but at every juncture, Nalla does him a favor which leaves Ars with a heavy heart. The next morning, Ars takes a taxi without waking Nalla in order to find his own way to Chennai. However, Ars realizes that the floods have blocked most of the roads and even the train station is covered by high levels of water. He gets mugged by a thief in the station who offers to help Ars with his luggages, and loses all his money. Nalla however comes to the station and helps Ars retain the wallet, sans the money. It is then revealed that Nalla is a trade unionist and is travelling with a cheque worth Rs. 30 lakh to be delivered to some people after fighting a court cases for some union workers. The comical and misunderstanding events continue as the pair make it to a different train station. There, Nalla decides to tell the story of his own past, but a tired Ars falls asleep and walks away as he is about to begin.
The film ends with Nalla walking away with his dog, Sangu.