Kaadal Kottai (1996)
Kadhal Kottai's director, Agathiyan, earned cult status after he razed down conventional rules of love in this film. He made his lead pair fall in love without ever having seen each other. While fresh-faced Devayani lived in Ooty and wrote letters, Ajith worked in Jaipur, handling his fiercely attracted boss, Heera as well.
The film has a nail-biting climax, which spawned dozens of clones. It won Agathiyan the National Award for best direction, and firmly earned superstar status for both Ajith and Devayani.
Also read: When Rajni was Billa