Ramalingam and Sundaralingam are orphans who take care of orphaned children. Sundaralingam paints shop banners and calendars. Ramalingam makes money usually by fraudulent means. Sundari, an arts student, falls for Ramalingam. Her friend Janaki falls in love with Sundaralingam. Janaki's father Paramasivam objects to Janaki's wedding since Sundaralingam is poor, prompting Janaki and Sundaralingam to marry with the help of their friends.

Days go by, but Paramasivam still does not agree. This causes Sundari to ask Janaki to lie to Paramasivam that she has given birth to a son. Paramasivam, upon receiving the letter, changes his mind and gets ready to set off to Chennai. Sundari lies to her Chicago-based father Balamurugan that Ramalingam is a rich man. Janaki, to easily convince her parents, also fabricates a story that Sundaralingam has become rich. The girls rent a bungalow for three days; the owner Noorjahan mistakes Janaki and Ramalingam to be a couple.

Balamurugan, who is supposed to come on that day, misses his flight and is unable to come over. Janaki's parents wish to surprise her, and they end up coming on that day. Ramalingam mistakes Janaki's father to be Sundari's father, and a comedy of errors ensues. Unable to tell the truth because of Noorjahan's presence, Janaki and Ramalingam let the mistaken identity stay as such. To keep the tale running, Janaki and Ramalingam introduce Sundari as the maidservant and Sundaralingam as the cook. Sundari borrows a child from a beggar woman, who stays in the house as the woman who supplies milk.

The four of them strive hard to hide the truth from Janaki's parents. While these happenings unfold, Varadhachaari, Paramasivam's friend, who knows the truth, comes over. The couples try to salvage the web of lies they have built, by skilfully getting Varadhachaari and Paramasivam to agree. Unfortunately, they then meet with Janaki's maternal uncle Singaram, a doubting Thomas, who begins to suspect the veracity of the stories of the youths. All the same, he fails to convince his sister and brother-in-law of the possible untruths they have been led to believe.

Now that Balamurugan too is about to meet them, Paramasivam himself steps in to help them build a story involving Balamurugan's daughter, who, to him, is a maidservant in the house. He concocts a complicated tale where Ramalingam is his son, Janaki and Sundaralingam reprise their real relationship and, worse, V. Anand, the former godman Ananda Vikadanantha, to be his cousin. The real reason Anand is at their place, is to hide from the police, as he is wanted for his fraudulent ways. Soon enough, the elders begin to smell something fishy. To end the mess, Sundari reveals the complete truth to everyone. Singaram reveals to all that Anand is a crook and Ramalingam is now forced to prove his innocence.

A chase ensues when Anand is held hostage by his ex-partner Junior Vikadanantha for money which he looted. Inspector Chokkalingam arrives in time to find Ananda Vikadanantha and Junior, and Ramalingam is proven innocent. Paramasivam accepts Janaki and Sundaralingam, and Balamurugan is happy about Ramalingam and Sundari.