Aarya plays the lead role of an Aghori devotee named 'Rudra' which probably is the least humane character that any actor would dare to do. Shiva is the lord of elimination in Hindu texts, and an Aghori who is an ardent follower of Shiva believes in 'Dushta nigraha' or elimination of the evil. Aarya has done fair justice to the role and Bala has exploited him in his looks and acting potentials. Bala seems to have spent enough time in studying the life style of the Aghori sects and beggars. That reflects in the eventual realism that results.
Cold blooded action and shocking pragmatism may disturb the audience. So you have to prepared for 'anything' and 'everything'. Cinematography is a chilling package of the movie and every face that comes along in the movie appears real and original to the plot. Music by ilayaraja is definitely fitting to the scheme.
Violent imagery is objectionable to minors and women. So it's not any family 'go-watch'. But the movie is well told, and questions the true nature of Kadavul- the God and repeating statements made by Rudra-'Aham brahmasmi' surely keeps you thinking.
If you can appreciate the alternate thinking that the director has convincingly achieved in the movie then go and give it a try.