Based on the Charles Bronson starrer Death Wish, Naan Sigappu Manidhan offers a twist on the traditional vendetta tale. Here too, a man loses his sister and his mother to the villains. But instead of going after the villains to extract revenge, he goes after ALL bad guys. He turns into a self-styled vigilante, ridding the streets of rowdies and goondas.

Vijay(Rajnikanth) is a tamil professor living with his widowed mother and his sister. He is in love with Uma(Ambika), a lawyer. During a visit to his friend Ravi's('Nizhalgal' Ravi) house, he is disgusted by goings-on in his neighbourhood. Illicit liquor is being sold at a tea-stall while prostitution is flourishing in another house in the same colony. But his complaints to the police yield nothing since the policeman is on the villains' payroll and manages to warn them before making a raid. When Ravi's sister is raped and killed and the perpetrator Mohanraj(Satyaraj) gets off scot-free with help from a minister, Vijay and Ravi take matters into their own hands and clean up the tea-stall and brothel on their own. Wanting to teach Vijay a lesson, Mohanraj and his goondas rape his sister(who then commits suicide) and kill his mother. Vijay then turns into a vigilante, walking the streets at nights and dealing out his own brand of justice - shoot first and ask questions later - to the rowdies and goondas. He soon becomes known as Robinhood, helper of the poor and the police sends Singaaram(Bagyaraj) to unmask Robinhood.

This is not an easy movie to watch. The body count is quite high and the two rape scenes are long and brutal. The atmosphere is serious (atleast whenever Bagyaraj is not around) and anybody picking this movie with the intention of watching a light-hearted movie like many of Rajnikanth's other movies, will be sadly mistaken. The mood of the movie can be illustrated by the fact that two actors, Y.G.Mahendran and 'Venniraadai' Moorthy, who have traditionally donned comedian roles, are villains here.

Right from Mullum Malarum, Rajnikanth has shone in roles where he is an affectionate brother showering love on his sister. Here too, the few scenes he shares with his sister in the beginning are soft and illustrate their closeness well. The picturisation of Kanne Naan... is sweet, especially when Rajnikanth brings in a whole troop of doctors when his sister pricks herself with a thorn. This brother-sister relationship is surprisingly effective in the short time it is shown. The romance between Rajnikanth and Ambika too has some nice moments.

The movie is involving and kept moving at a fairly good pace by director S.A.Chandrasekharan. Rajnikanth shooting down the criminals doesn't get too repetitive due to the variations in the situations. Background music by Ilaiyaraja during these scenes is especially effective. The movie also perks up after Bagyaraj's introduction. With his casual attitude, he infuses life into the film. Though it is not clear how he shows up at Rajnikanth's college in the first place and how Rajnikanth seems to know him, his later deductions about Rajnikanth's second identity are quite clever.

The climactic court scene is completely cinematic with Bagyaraj having fun in the witness stand. He has some nice lines about how the hands of the police are tied when it comes to bringing criminals to justice. There is also a scene in the judge's house which is rather unexpected and somewhat clever. The director probably had a tough choice to make on the judgement to be delivered. While arbitrarily releasing Rajnikanth would have seemed like a mockery of normal judicial proceedings, punishing him would not have been an option since he was the hero with quite a rabid fan following. He has resolved this rather cleverly.