Thangamana Thangachi (transl. Precious sister) is a 1991 Indian Tamil-language drama film directed by Senthilnathan. The film stars R. Sarathkumar and Aamani (credited as Meenakshi) while Mansoor Ali Khan, Ragapriya, Jai Ganesh, Senthil, and K. R. Ganesh, among others, appear in supporting roles. It was released on 15 January 1991.^[1]

This article needs an improved plot summary. (January 2023)

Vijay and Seetha are siblings. After their mother's death, Vijay worked hard to come up in life. He brought up his sister alone. Many years later, Vijay becomes a taxi driver. Seetha falls in love with the postman Kannan, while Vijay is in love with his childhood lover Lakshmi. Lakshmi is the daughter of the corrupt politician Marappan, and her brother rapes the young girls as he wishes. At Seetha's wedding, Lakshmi's brother kidnaps Seetha and then rapes and brutally kills her. Vijay decides to take revenge.

The music was composed by Shankar–Ganesh, with lyrics written by Kalidasan.^[2]

C. R. K. of Kalki wrote ^{[clarification needed]}.^[3]