Naan Sigappu Manithan is a 1985 Tamil-language vigilante action film directed by S. A. Chandrasekhar and produced by A. Poorna Chandra Rao under Lakshmi Productions.
The film stars Rajinikanth, K. Bhagyaraj, and Ambika, with Vijay playing a child artist role. The movie is a remake of the Hindi film "Aaj Ki Awaaz".
Ilaiyaraaja composed the music for the film, while M. Kesavan handled cinematography and P. R. Gautham Raju edited it.
The story follows Tamil professor Vijay, who lives with his widowed mother Lakshmi and sister Shanti. He encounters corruption in his friend Ravi's neighborhood involving illicit liquor and prostitution. When he files a police complaint against this, the corrupt officers ignore it but later receive a warning before attempting a raid to suppress the illegal activities.
Following this incident, Ravi's sister is killed by the same criminal element led by Mohanraj. Despite evidence, Mohanraj escapes punishment with the help of a minor official (minis).
The film was released on 12 April 1985 and became a box office success.
