Neeya (1979)

Kamal Haasan along with his group of friends: Vijayakumar, Srikanth, Jaiganesh, Ravichandran go to a forest. Kamal is a researcher who studies about the behaviour of snakes (Ichadhari), a kind of snake which takes humanoid form. One of his friend kills the beloved of the serpent, Sripriya, despite the intervention of Kamal. Initially all the other friends ignore Kamal without knowing the seriousness. They all leave the village and the female serpent (Sripriya) vows to avenge for the death of her beloved. She kills all the five friends of Kamal in disguise at some instance and at the end she disguises as latha (Kamal's love interest) to in order to kill him. In the end Sripriya is killed and Kamal reunites with Latha and the child of Srikanth.