The film opens with Kinathadi Kaali (Ramya Krishnan) establishing her powers with a couple of sequences, including reducing a screen scorcher (Nassar) to a pale shadow. Cut to the present, Priya (Keethika), the intelligent daughter of Pichumani (Ramji and Gayathri (Sangeetha), who treat her like the apple of their eyes. Soon, she is possessed by the spirit of Savithri (Kaveri), who is ditched by her fiancé Nanjappan (Riyaz Khan). With the help of Kaali, it is the now the turn of Savithri and her brother Karuppu (Ganja Karuppu) to take revenge. How they punish Nanjappan and his sorcerer friend Mandiramoorthy (Shafi) is the rest of the story.

Kottai Mariamman is a Tamil devotional film directed and produced by Rama Narayanan. The film featured Roja in the title role alongside Karan and Devayani, while Vadivelu plays a supporting role. The film, which had music composed by Deva.