Kumar (Dinesh Master) works for the cleanliness of the city, but Poonkodi (Manisha Yadav), his wife, is tricked into the marriage by her father who is impressed by Kumar's character. She believes that her husband works as a clerk, but life takes an ugly turn when she finds out about his actual occupation.

The film begins with the note, 'Inspired by true events' and also tries to address the popular saying, 'To err is human, to forgive is divine'. When the film begins, we know we have a message to take home, but how much of it do we really take away? Director Kaali Rangasamy confuses us at different junctures, as he portrays the reality of life with a scene where the protagonist gives his mom a bottle of alcohol to provide a relaxing end to her day but also writes a cliched and unfunny scene where an obese woman is used to precipitate laughter.

As the conflict in the film is revealed and the sub-plots open up, we expect to see some light at the end of the tunnel. But the execution in the second half of the film falls short of what was promised at break-point. OKK is a film, that we usually expect to be driven by the main characters. Here, we have Dinesh Master who fits the bill perfectly but delivers a mediocre performance. We also have a typecast Manisha Yadav, who attracts some attention by putting up a decent show.

On the other hand, obviously playing the role of the protagonist's comical best friend, Yogi Babu manages to trigger some laughs and he creates his trademark moments. The two friends, who played the antagonists deliver weak performances and the director could have extracted good work from them.

As more characters are introduced, we seem to find their purpose almost immediately. The story starts to travel on the path always taken, giving us a chance to predict the following scenes. Oru Kuppai Kadhai is exhibit-A of the kind of script that has the substance to do well, but whose execution falls just above average.

Joshua Sreedhar's songs are passable, while Deepan Chakravarthy's violin-dominated background score does elevate certain scenes. Magesh Muthusamy's cinematography is modest and Gopi Krishna's cuts could have been precise. One might be baffled by the 'U' certificate, as some rape scenes and violence is palpable.