The film revolves around the story of a young girl Shweta taking her first steps towards adulthood. Ready for the adventure, the thirteen-year-old is upbeat. However, she soon discovers that every night, her uncle Gautam (Kushboo) transforms himself into a woman to lead a completely different life. When Shweta confronts Gautam on the matter, Gautam tells her he wishes to run away and marry Aravan at a local festival, the Koovagam Festival.
The festival is held annually, where people of the third gender regularly meet to re-enact the story of Aravan, a character from the epic Mahabharata. Shweta decides to find her uncle and bring him back home, and along the way, she makes new friends of the third gender and discovers a whole new culture.