The plot starts off with the murder of Jennifer, a ballet dancer. Thanks to a few evidences and assumptions, all fingers point to Siddharth, the son of Vijay Raghunath, a business tycoon. Vijay is worried over his son’s future as the latter’s engagement has been fixed. He seeks the help of his adopted son, Sai Prasad, a crime branch officer. Prasad starts investigating the issue with the help of his assistant, Bhaskar. The investigation takes them to Gautham Krishna, an RJ in a private FM station, and his neighbour Pooja. Prasad is after a confidential DVD which was once possessed by Gautham’s friend, who is no more. Knowing that the DVD is with Pooja, the henchmen set by Prasad kidnap her and start following Gautham’s movements. Gautham, who gets a lead about Pooja from his pet Siberian Husky, Blackie, rescues her, and the two set out to solve the mystery of the case, with the help of Peter S. Kumar, a former police officer.
In April 2016, it was announced that Shakthi would feature in a new film titled 7 Naatkal directed by his cousin Gautham and written by his uncle, Vimal peethambaram. The film production started on 21 April 2016, with Nikesha Patel, Ganesh Venkatraman and Angana Roy revealed to have joined the cast. M. S. Prabhu joined the team as a cinematographer, while Vishal Chandrasekhar was signed on as the project's music composer. Contrary to reports, Ganesh revealed that he portrayed an Antagonist role and stated that the film would be a "racy thriller" which takes place over seven days as per the title. The first schedule was shot across Chennai, while the team also nurtured plans to shoot songs abroad.
Soundtrack
The soundtrack was composed by Vishal Chandrasekhar, and lyrics written by Madhan Karky. Behindwoods rated the soundtrack 2 out of 5.
Times of India wrote "7 Naatkal has its moments, especially in the first half, with a few light-hearted scenes which gradually build up to an engaging suspense drama." News Minute wrote "The film struggles to entertain with flat comedy, badly constructed song sequences, and attempts to score on the emotional quotient with some blah sentimental scenes as well."
