The story starts in the 9th century. King Raja Raja Chola presents his valuable sword to his commander-in-chief, for playing a vital role in winning a war. It was preserved by his family descendants. This information was known by an archaeologist, who plans to steal it due to its monetary value. Presently, Gemini Ganesan is charged with the care of the sword.

The villain plans to send Raja to do this job. He enters into the palace as the son (who ran off from the family in his childhood) of Kumarasamy, Gemini Ganesan's son-in-law. Initially, everything goes smoothly. However, Indhu, Gemini Ganesan's granddaughter, falls in love with Raja. The situation called for Raja to marry her. Later, Indhu discovers the truth and confronts him about stealing the sword.

In the meantime, Gemini Ganesan, not knowing Raja for what he came there for, gives the sword to him and asks him to look after it. This makes Raja realize his mistake and promises him to protect it. The climax occurs when Raja manages to protect the sword from the villain, and the family accepts Raja after learning the truth.