Arjun Krishna is a technician in a Chennai-based BMW showroom, who meets Anamika Raghunath, a college student, while she is out with her friends at Hard Rock Cafe.

The CCTV camera installed at the apartment does not show any men arriving and taking away Anamika, prompting Arumugam to suspect that Arjun has lodged a false complaint as he is drunk.

Arumugam and Arjun rush to Raghunath's mansion, where they see him being threatened by the two men who had kidnapped Anamika as well as the police inspector of Besant Nagar to give them a SD card which has some critical information.

The two men contact their boss, who is the right hand of the Union Minister for Communications and Information Technology and potential Prime Ministerial candidate Rishi Dev.

The video shows the murder of model-turned-actress Megha Sharma at the hands of Rishi Dev two days ago and how he had fabricated the incident to make it look like the actress died due to a gas leak at her mansion.

Rishi Dev also lodges a false complaint against them to the police commissioner Arulraj, claiming that they killed Raghunath to get his money and also to fuel Anamika's "drug-addiction".

Anamika, in incognito, manages to contact every leading media house to assemble at the Forum Vijaya Mall (where they are hiding) at 3 pm as there is going to be a "sensational event" there.

The police take advantage of the media assembled at the mall and claim on live television that Arjun and Anamika are murderers, announcing a ₹5 lakh reward for those who capture them.

But before he can get out the truth, the police arrives, following which Rishi Dev destroys the mobile phone and beats him up, all the while revealing that he killed Megha Sharma, but he cannot do anything about it because he is going to be arrested for the attempted murder of a Union Minister.

[8][9] It continued its successful run by remaining in first place for a second consecutive week despite new releases and subsequently went on to record profits at the box office.

And, yet, there is enough cleverness in the writing and assuredness in the execution, especially for a debut film, to make Arima Nambi stand apart from your usual action thrillers".

[12] S. Saraswathi, writing for Rediff.com said, "A skilfully written plot, deft direction and excellent camera work make director Anand Shankar's Arima Nambi a highly engaging, action-packed thriller", and gave it 3 stars out of 5.

[14] Deccan Chronicle, giving the film 2.5 out of 5 stars, wrote, "Anand Shankar has chosen one (...) intelligent plot with Vikram Prabhu helming the affair, which is gripping in parts".