In 1279 A.D., the downfall of the Chola dynasty seems imminent as the Pandyas drive the Chola people out of their kingdom in southern India. To escape them and save the life of his successor, the Chola emperor sends his son, his royal advisor (Raja Guru), and the remaining Chola people to a secret territory. The refugees take along an idol sacred to the Pandyas, angering them. To capture the escaped Cholas and the stolen idol, the Pandyas extend their invasion to unexplored territories, but are unable to find them.

Centuries later, in 2008, Indian archaeologists are searching for the secret land of the lost Chola group using clues left by the ancient Pandyan warriors, but the searchers always disappear. After the sudden disappearance of archaeologist Chandramouli, the government organizes a search expedition led by the cruel and arrogant officer Anitha to find him and what became of the Cholas. She is assisted by a detachment of the Indian army led by Ravisekharan. They recruit Chandramouli's estranged daughter, the aloof and quiet archaeologist Lavanya. She supplies crucial documents about the Chola dynasty prepared by her father, which contain route information. Anitha also employs a group of porters headed by Muthu, who she and the army continually ill-treat.

The expedition arrives at an island called Min-gua, on the borders of Vietnam, Thailand, and Malaysia. There they face seven traps set by the Cholas: sea creatures, which they flee from; cannibals, who cannot eat them as long as they do not look them in the face; warriors whose land they invade and who they brutally kill; snakes; hunger; quicksand; and a village. Many porters and soldiers die, Anitha forcing the porters, who she had not warned of the dangers, to carry on and emotionally manipulating Muthu into not retreating by insulting his masculinity.

Muthu, Anitha and Lavanya then become separated from the others. They reach a ruined village, where they realize that someone is following them. Under the influence of black magic, they are almost driven mad, and surrender to the follower, who reveals himself as the aged Raja Guru, the royal advisor who was sent away 800 years ago. The Chola people have become an ethnically isolated primitive Tamil group ruled by Rajendra Chola III. They are living in poverty and suffering from drought while awaiting the arrival of the messenger who, it is foretold, will lead them back to their motherland of Thanjavur. When Muthu, Anitha, and Lavanya strip in front of themselves in front of the Raja Guru, a tattoo of a tiger is revealed on Muthu's back.

After Muthu, Anitha, and Lavanya are revived to consciousness by the Raja Guru, other priests and physicians. Consulting the gods for omens, the king and priests are told that one of them is a Chola, one is a Pandya, and one is a commoner. The king and Raja Guru hypnotize Muthu, attempting to have him reveal himself as the messenger, but the king rejects the possibility because of Muthu's appearance and his incoherent babbling, and orders all three to be burnt alive as sacrifices.

At this point Anitha suddenly pricks herself and uses her blood to perform black magic. She tells the king that she is the messenger. All the Chola people are ecstatic. Muthu and Lavanya are enslaved.

Unbeknownst to the Chola people, it is revealed to the audience that Anitha's account of her ancestry reveals her true identity as a descendant of the Pandya Dynasty. On glimpsing the Pandyas' sacred idol, she cries out. The minister sponsoring the expedition and Army officer Ravishekaran, who escaped the traps and is the sole survivor of the expeditionary force, are also revealed to be Pandyas. Anitha attempts to seduce the king and to persuade him to march immediately to the homeland so he can be formally crowned there, but he grows suspicious since her actions do not match the traditions about the messenger. The prophecy was that on arrival, the messenger will be beaten, it will rain, and finally, he will console the destitute. Giving up on persuading the king, Anitha attempts to kill the Raja Guru and poisons the wells, then hypnotizes a Chola girl into passing information to Ravishekaran, who returns with reinforcements. The king, horrified that he ever believed in her, realizes that Muthu is the true messenger. The Raja Guru gives all of his magical powers, including invisibility and invulnerability, to Muthu and dies.

The Cholas fight bravely against Ravishekaran's troops but are overwhelmed by modern technology. Rajendra Chola III and his people are taken prisoners, their women raped by the soldiers. The king dies, and the remaining enslaved Cholas drown themselves in the sea with his body. Muthu then breaks free from his shackles, and saves the king's son, the last remaining heir of Chola dynasty. Using the powers given to him by the Raja Guru, he escapes from Anitha and the army with the Chola prince, presumably to India, thus fulfilling the prophecy that the messenger will take the seed of Chola dynasty to their homeland.