Naalu Polisum Nallairutha Oorum (NPNO) begins with a tour of Meiyur, the village where the film is set in. It is a model village where everyone is friendly with one another. The villagers are very accommodative and considerate — when a thief (Yogi Babu) who had come to rob the temple breaks a leg in the process, they do not beat him up and hand him over to the police; instead, they advise him, 'Paathu thirudunga' and mend his broken bones. But most of all, they are virtuous, so much so that they leave a gold chain on the road for two days in the hope the person who lost it might come and find it. This honesty is what has resulted in the village receiving the Best Village award from the president for five consecutive years.

This integrity is also what has made the police station in the place redundant — we see a board there saying 'Sunday Holiday'! The station exists mainly as a recreation centre for the four cops, who while away their time watching cricket on the TV or playing carom. And once in a while, they are of use to the villagers who might need help in finding their cows. So, when a letter arrives saying that they are to be transferred to Ramanathapuram, a hotbed of violence, the cops are, naturally, reluctant. And they hatch a plan to register a crime, so that a police station becomes a necessity for the village. What they don't realize is that their actions might have far-reaching conclusions that will not only affect them but also the entire village.

The central conceit of NPNO — cops trying to stage a crime to retain their jobs — is taken from the 1939 film Ask A Policeman, and the team has been smart enough to acknowledge it in pre-release interviews. While that film uses the premise for a whimsical comedy that is distinctly British, debutant NJ Srikrishna uses it to tell a conventional story with an even more familiar message that involves Newton's third law.

The first half is engaging enough as we are introduced to the place and the characters, including the four cops played by Arulnidhi, Singampuli, Bhagavathi Perumal and Rajkumar. Though Arulnidhi, as the hero gets a cheeky introduction scene (in true masala movie style, where bullets bend and bounce off things to hit their targets) and a romantic track (that is very blah), it is Singam Puli who comes across as the protagonist. He gets to be in most of the scenes and his antics in these portions are quite hilarious. The skit-level humour is entertaining for a while, but after a point, we start wishing for little more sophistication in the writing and filmmaking (which is in TV drama territory). But the second half is more of a letdown, mainly because the director has difficulty in maintaining the tone of the film, which abruptly changes from farce to realism (read preachy), and by the time we reach the bleak — and abrupt — ending, we feel as if we have ended up in a different film.