Kovalan is the son of a wealthy merchant in Kaveripattinam and married Kannagi (CR Vijayakumari), the lovely daughter of another merchant. They lived happily in Kaveripattinam until Kovalan fell in love with the courtesan Madhavi (Rajasree). His infatuation causes him to leave his wife and spend all his wealth on the courtesan. But at last, in a penniless state, Kovalan realises his mistake, and returns to Kannagi. Kannagi give him their only remaining asset, a pair of anklets filled with precious gems. Kovalan and Kannagi move to the great city of Madurai with this capital and hope that they can recoup their fortune in trade.
Madurai was ruled by the Pandya king Neduncheziyan. While on his way to sell the anklet in Madurai, Kovalan is held by the king's guards for the alleged theft of the queen's anklets. On the king's orders, he was beheaded without trial for this crime. When Kannagi hears of this, she furiously sets out to prove her husband's innocence to the king.
In the king's court, Kannagi breaks open the anklet seized from Kovalan to show that it contains rubies, not pearls like the queen's anklets. Realizing their error, the king and the queen die of shame. Unsatisfied, Kannagi curses that the entire city be burnt and due to her utmost chastity, her curse comes true.