Pulan Visaranai (transl. Investigation) is a 1990 Indian Tamil-language action thriller film directed by R. K. Selvamani. The film stars Vijayakanth. while Rupini, M. N. Nambiar, Radha Ravi, Anandaraj, and Sarathkumar play supporting roles. The film, produced by R. Sundar Raj and S. Raveendran, had musical score by Ilaiyaraaja and was released on 14 January 1990. It was remade in Hindi as Ravan Raaj: A True Story (1995). The character of the antagonist Dharma (played by Anandaraj) is loosely based on the serial killer Auto Shankar. A sequel, Pulan Visaranai 2, was released in 2015.