Prashanth, Aishwarya Rai
A. R. Rahman
Nachiappan (Nassar) is a restaurateur in Los Angeles, USA. His twin sons Vishwanathan (Visu) and Ramamoorthy (Ramu) (both played by Prashanth), are medical students, who help him out in the evenings and on weekends, alongside with the restaurant's chief cook, Juno (Senthil). One evening, Vishwanathan goes to the airport to check on the family's supply concession and sees that some fellow Indians – Madhumitha (Aishwarya Rai), her brother Madhesh (Raju Sundaram) and their grandmother Krishnaveny (Lakshmi) – have difficulty with an address. He pitches in to help and learns that they just flew in from India so that Krishnaveny can undergo a crucial surgery to remove her brain tumour.
The story shifts to the hospital where Vishwanathan, an intern, visits Krishnaveny's room after the operation, and notices she has been operated on the wrong side. Vishwanathan appeals aggressively to the doctors and has the error corrected by another surgery and then spearheads an angry fight for compensation. The hospital compensates $2 million avoid a messy court case.
When the grandmother realises that Vishwanathan and Madhumitha have fallen in love, she extends the family's stay in the United States and takes a liking to Vishwanathan's good nature. However, Nachiappan objects to the budding romance and wants his sons to marry identical twins because he himself has an identical twin brother, Pechiappan (Nassar). They both had married for love in their youth, but are now estranged because Pechiappan's wife Sundaramba (Raadhika Sarathkumar) showed such tyrannical behaviour towards Nachiappan's wife (Geetha), that the latter died delivering the twin boys.
Krishnaveny tries to solve the problem by telling Nachiappan that Madhumitha has an identical twin, Vaishnavi. The story spun by Krishnaveny is that Vaishnavi has been brought up in an orthodox Brahmin household. At this point they ring in Madhumitha's alter ego, contrasting Madhumitha with a very demure, typically traditional Indian version. Ramamoorthy, falls for the act, unaware that Vaishnavi and Madhumitha are the same person. Meanwhile, Pechiappan arrives to a warm welcome by his brother, but later attempts suicide. Nachiappan then rescues him and comes to hear of his sad story and comes up with a plan. Accordingly, Nachiappan and his brother switch places. Nachiappan goes to his brother's wife and impersonate as his brother to reunite with her.
He succeeds. Nachiappan's brother impersonated as Nachiappan. Ramamoorthy then meanwhile, figures out that Vaishnavi is Madhumitha and she was impersonating Vaishnavi. Vishwanathan in anger immediately leaves Madhumitha's household along with his family, but Ramamoorthy persuades his father who is not actually his father to have Madhumitha and Vishwanathan married. Though Ramamoorthy did not know it was not his father he talked about his father's brother who was right there impersonating. That made him guilty. He decided to have Vishwanathan married to Madhumitha. When Nachiappan figured out that Madhumitha doesn't have a twin,he goes and stops the wedding. There they figure out that the brothers impersonated each other as well to get along. Nachiappan's brother's wife persuades Nachiappan to have them married because Madhumitha did the same thing the brother's did. In the end, Visu and Madhu get married.