The movie starts with a flashback, portraying Nandini and Aditha Karikalan’s childhood. A young Nandini and Aditha Karikalan love each other. Kundavai did not like Nandini and doesn’t want Nandini to be her sister-in-law, but Aditha Karikalan and Nandini were sure that their love will last forever and they will get married and lead a happy life. As time passes, one day Aditha Karikalan took Nandini with him to his palace to introduce her to his family and let them know that she will be the future queen of the kingdom as he is going to marry her. Their romance is discouraged by princess Kundavai and Sembiyan Mahadevi, who consequently expel Nandini and her foster family from the kingdom while Aditha Karikalan is at war and becomes unaware of this. When he returns he is shattered to know that Nandini left the place without telling him and started to search for her everywhere. Nandini is said to have subsequently been taken in by Veerapandiyan, the Pandya ruler.
In the present timeline, Arulmozhi Varman alias Ponniyin Selvan’s presumed death disheartens the empire; Parthibendran Pallavan meets with Nandini on the coast and she manipulates him to misdirect Aditha Karikalan to Kadambur for the apparent well-being of the empire. Ravidasan and other members of Pandya Aabathudavigal wish to make sure that Ponniyin Selvan is dead. Vallavaraiyan Vandiyadevan and Poonguzhali row with a surviving and severely ill Ponniyin Selvan, who recollects being rescued by Oomai Rani from being drowned in the sea. They chance upon Azhwarkadiyan Nambi and Sendhan Amudhan, who suggests rushing Ponniyin Selvan to Buddhist monks for treatment. They see Ravidasan and his fellow perpetrators approaching and hence, Vandiyadevan misdirects them and gets himself seized. Elsewhere, Madhurantakan proclaims himself as successor to the throne, receives support from Shivan Adiyars and allies with Khottiga, the Rashtrakuta king, who desires to avenge being defeated by Aditha Karikalan in a battle by marrying his daughter.
Starring: Vikram, Aishwarya Rai Bachchan, Jayam Ravi, Karthi, Trisha