Kazhugu
Raja, an atheist, is constantly at a war of wits with his brother who is a firm devotee of a god man. When tragedy strikes, disturbing facts are revealed, leaving everyone shocked.
Starring Rajinikanth, Rati Agnihotri, Cho Ramaswamy, Y. G. Mahendran, Thengai Srinivasan, Sangili Murugan, Senthamarai, V. K. Ramasamy, S. V. Ramadas, Vanitha Krishnachandran
Watch "Kazhugu" from streaming services Amazon Prime, Amazon released in 1981. It's a action & adventure and thriller movie, and has a rating of 6.4 out of 10 from Imdb which is usually fine for this kind of movie.