Kaivantha Kalai is a South Indian Tamil film Written and directed by Pandiarajan released in 2006. In this film Pandiarajan introduces his son Prithivi rajan. The film received mixed reviews.
Kannan(Prithvi) is in league with his father(Manivannan) in duping the people in his village. He comes across Kausalya(Sruthi), a timid, schoolgoing Brahmin girl and falls for her immediately.
From his grandfather he learns that Kausalya's mom is his father's sister and becomes even more determined to wed her. Kausalya begins to like him too but asks him to mend his ways before they can get married.