A police constable, Aarumugam (Kaali Venkat) talks to the new Sub Inspector, Arjun (Vijay Yesudas) about Maari (Dhanush), a local rowdy, who rose to fame after killing a rival rowdy. Maari is an irritating guy, who along with his henchmen Sanikilamai (Robo Shankar) and Adithangi (Kalloori Vinoth), constantly pesters the people in the area and extorts money from them. His main line of work is in training racing pigeons. His boss is Velu (Shanmugarajan), a bigger don who also is involved in the pigeon races as well as the smuggling of sandalwood.
Maari constantly has fights with "Bird" Ravi (Mime Gopi), another local rowdy who is also working under Velu. One day, a lady named Sridevi (Kajal Aggarwal) enters the business, trying to open a boutique in Maari's area. Maari forcefully becomes her partner in the business, which angers her after she loses some customers. She decides to help Arjun to catch Maari by getting close to him, pretending to fall in love with him and incriminating him with evidence of his confession: he had tried to kill the rival rowdy, but failed. She shoots the talk with Maari in the drunken state, who describes about the murder.
Somebody else had killed him, and he took the credit. Maari is soon arrested by Arjun. 6 months later, when he is released, he finds out that Velu also has been arrested, and that Arjun is actually a corrupt cop & he and Ravi are working together and have arrested some people in the area under the pretext of smuggling, to extort money. Maari decides to take revenge on the duo. He first frees the local people from the extortion by Ravi's gang, while Sridevi also falls in love with him for real.
Later, he captures one of Arjun's smuggling vehicles and the driver, while forcing him to release Velu. When Arjun takes revenge by burning the pigeon coop of Maari, which kills 10 of his pigeons, he gets angry and beats up Ravi and Arjun, with the former agreeing to confess to everything. Angered, Arjun stabs Ravi but eventually gets arrested by the Revenue Department after Aarumugam reveals all of his secrets. Finally Sridevi approaches Maari to confess her love, which he rejects, returning to pester the local people and extort them for cash.
The collaboration between Listin Stephen and Raadhika Sarathkumar's production house and director Balaji Mohan was first revealed in early January 2014, with Dhanush and Kajal Aggarwal being signed on to be a part of the "romantic entertainer". The first look poster released later indicated Dhanush was a co-producer of the film. Mohan wanted the film not to be a bilingual like his previous ventures as he found the process difficult to shoot the same shot twice and to retain the same energy in both of them. He said in an interview in March 2014 that he narrated a one-liner to Dhanush, on whose consent, he would develop the complete script after releasing Vaayai Moodi Pesavum (2014), adding that this film would "definitely not be a love story". Dhanush said in early August 2014 that the project was in its pre-production stages. Anirudh Ravichander, who was supposed to work with Mohan for Vaayai Moodi Pesavum, was selected as the film's music director marking his fifth collaboration with Wunderbar Films. Prasanna, an assistant of A. Sreekar Prasad, was signed in on as the film's editor while Om Prakash undertook the cinematography. Vijai Murugan was signed in on as the film's art director. On 7 November 2014, Mohan announced that the film was titled Maari.
Dhanush was initially rumoured to be seen as a tailor living in north-Madras in the film. Sources close to the film's unit later said that he would be seen as a local slum chieftain for which he had to speak in Madras accent. His character was later revealed to be a person who is in into pigeon racing, similar to the one he played in Aadukalam (2011) where he was seen as a person dealing with rooster fights. Kajal Aggarwal, who was supposed to work with Dhanush in Polladhavan (2007), was cast on Dhanush's insistence, who wanted to gain a foothold in Telugu cinema by cashing in on Aggarwal's stardom there. She said in an interview that she overcame her fear of birds due to her experiences with pigeons during the film's shoot. Although Kajal Aggarwal was signed during the film's initial stages of production, she joined the sets in November 2014. Robo Shankar, one of the cast of Vaayai Moodi Pesavum, was signed in on for an important role. Playback singer Vijay Yesudas joined the team in December 2014 making his debut as an actor in Tamil cinema. He stated in late February 2015 that he would play the role of a police officer. Anirudh made a cameo appearance in the film and joined its sets in mid March 2015.
Principal photography began on 4 November 2014 at T. Nagar in Chennai. The film's second schedule began on 25 November 2014. By 11 December 20 days of the film's shoot was done including a montage song. A special set was erected at Valasaravakkam, Chennai where portions of the film including a song and a fight sequence were shot for 20 days continuously from 23 December 2014.
By 8 January 2015, half of the film shoot was completed which included two songs. The team planned two short schedules, one before Pongal and one around 20 January 2015 for 5 days. Filming continued at a market area in Triplicane during early February 2015 and a similar set was erected in Chennai to shoot major portions of the film. The film's shoot was wrapped up by 21 February 2015 in four months. It was later known that 20% of the filming is remaining for which the film's team left for Tuticorin port to shoot the film's last schedule. The song "Thara Local Boys" featuring Dhanush and Anirudh was shot in mid March 2015. Dhanush confirmed the completion of principal photography on 15 March 2015 through his Twitter page.
The film was released on 17 July 2015.
The film was a commercial success, grossing a lifetime revenue of ₹80 crore on a budget of ₹25 crore. It is Dhanush's highest-grossing Tamil film till date.
Maari received mixed reviews from critics, who praised the soundtrack, production value, and performances of Dhanush and Robo Shankar, while criticized the director for making a routine masala fare and deviating from the offbeat comical tone of his previous two directorials
Baradwaj Rangan wrote, "Save for the bits with Robo Shankar, the writing is shockingly ordinary — lots of tell, very little show...Does making a mass movie mean that you forget to make an interesting one?" The Times of India gave 2.5 out of 5 and wrote, "If you, like many others, had been excited about Maari after watching its trailer, be prepared for disappointment. Almost all the best bits from the film are already in the trailer and the film clearly lacks the crackling energy that we see in the trailer. Maari largely feels like one huge build-up without any proper pay-off". NDTV wrote, "A couple of mass moments and some quirky humor apart, there’s nothing in Maari to justify the much-anticipated Balaji Mohan- Dhanush collaboration". Indo-Asian News Service wrote, "the director isn't capable of delivering a wholesome commercial entertainer with some story, some heroism and some cliches a la Dhanush's recent blockbuster Vella Illa Pattathari. Except the story, we get everything else from Maari, and that's the biggest concern of the movie", with the critic adding that "Dhanush saves a very ordinary film". Rediff gave 2 out of 5 and wrote, "Uninspiring and predictable, director Balaji Mohan's Maari is just another mass masala movie created to idolise its hero". The New Indian Express wrote, "The director's attempt to go ‘commercial’ this time, concentrating more on his hero than the script, backfires. The film gives a sense of Deja vu throughout, the real interesting moments very few and far between", calling the film "a painful tedious experience, meant for hardcore Dhanush fans".
Behindwoods gave 3 out of 5 and stated "Maari is a very honest masala flick made to satisfy the mass audience". Sify gave 3 out of 5 by saying Director Balaji Mohan has made film with punch dialogues, slow-motion shots and an adrenaline pumping background score by Anirudh. It is a film that makes no bones, no pretenses about the fact that it is packaged for B & C audiences.
Anirudh Ravichander composed the film's soundtrack. Sony Music India released the soundtrack on 7 June. Behindwoods.com gave the album 3 stars out of 5.