Maan Karate is an Indian Tamil-language fantasy romantic comedy film co-written and directed by Thirukumaran, written and co produced by A.R.Murugadoss. Produced by P.Madan and co-produced by James for the banner "Escape Artists Motion Pictures". It stars Sivakarthikeyan, Hansika Motwani, Vamsi Krishna and Sathish in the lead roles. The supporting roles has Sayaji Shinde, Shaaji, Preethi Shankar, Ashwathy Ravikumar, Ravi Prakash, Soori, Swaminathan, Vikramadithyan, Arunraja Kamaraj, Rajesh Gopalan, Vinu Karthik, Yogi Babu and Tejaswini. Soundtrack and BGM composed by Anirudh Ravichander, Cinematography handled by M. Sukumar, Edited by Sreekar Prasad.

Plot: Five IT employees, Sandy (Sathish), Joe, Gokul, Vaishnavi and Nikita, meet a siddhar who has the power to grant wishes to those who request them, during a weekend trip to the Chandragiri forest. Sandy, who is sceptical about the siddhar's powers, asks him for a copy of the Daily Thanthi newspaper dated on the day after Ayudha Puja (no newspapers are printed during Ayudha Puja). To his surprise, the siddhar materialises the requested copy. The IT gang read the materialised newspaper and find out to their shock that the company which they work for (Satyam Computers) would close down the next day. When this does happen, they accept the credibility of the newspaper and decide to make money through it. While Nikita is reading the paper, she sees an article where one Peter who stays in Royapuram wins a boxing tournament on the day of Ayudha Puja and dedicates the prize money of ₹2,00,00,000 to the five of them. The IT gang is astounded on reading this news and decide to find this Peter and sponsor him for the boxing tournament, with the hope of getting ₹2,00,00,000, despite eventually finding out from the boxing association that the cash prize for the tournament champion is only ₹1,00,000.

The IT gang successfully manages to track down Peter (Sivakarthikeyan), but immediately find out that he is not a boxer, but an unambitious youth who just spends his time drinking and roaming around. However, he is in love with a young woman Yazhini Sethuraman (Hansika Motwani), who is a sports buff. To impress Yazhini, he accepts their offer to participate in the tournament. However, Peter does not show any inclination to train for the tournament, instead he uses the IT gang to fulfil his own desires, including winning Yazhini's heart, much to their chagrin. Later, the IT gang find out that there is another boxer named Peter (Vamsi Krishna) who also resides in Royapuram like the Peter they are sponsoring, but is a champion boxer who is even nicknamed as "Peter the Killer" as he had killed several opponents in the ring. Thinking that they are sponsoring the wrong Peter, the IT gang approach "Killer" Peter and offer to sponsor him, but he refuses. They reluctantly decide to continue sponsoring the Peter they are currently sponsoring.

Soon the boxing tournament starts and Peter somehow manages to win all the preliminary matches by fluke, by using a technique wherein he uses his nimble and agile body to escape being hit by his stronger and more experienced opponents, eventually causing them to inadvertently get disqualified or knocked out. The media give a name for his technique: "Maan Karate", which in English means, "running for life". Peter soon becomes known as "Maan Karate" Peter (to distinguish from "Killer" Peter) and becomes an Internet sensation overnight, winning a lot of fans. Due to Peter's rising popularity, the prize money is raised from ₹1,00,000 to ₹2,00,00,000, which excites the IT gang, who now feel that their dreams will come true with the Peter they are sponsoring after all.

After defeating some good for nothing boxers, Maan Karate Peter rises to fame. His photo appears in the front cover of Sportscenter and many other international sports magazines. People start wearing maan karate T-shirts and temples and churches conduct special events for the success of Maan Karate Peter. Eventually, Peter enters the final of the tournament, where he is to face "Killer" Peter. But even 88% of the people are confident that Maan Karate Peter will win it hands down and that world is at his feet. Peter becomes upset at this development, fearing that he might be killed by "Killer" Peter due to his lack of boxing skill. He tries to avoid fighting in the final through various means, none of which are successful. In a last-ditch attempt, he tries to convince "Killer" Peter to "throw" the match so that he could win and impress Yazhini, but is verbally abused and physically assaulted by him in response. Hurt at the treatment which "Killer" Peter meted out to him, Peter begins to train hard for the final with the sole purpose of defeating "Killer" Peter. Meanwhile, unknown to him, the IT gang who is sponsoring him switch over to "Killer" Peter's side after being offered ₹75,00,000 by "Killer" Peter's father-in-law, despite Nikita's reservations.

The final takes place on the day of Ayudha Puja. "Killer" Peter immediately gains the upper hand, pummelling Peter with heavy blows. However, Peter is not daunted and continues to put up a brave fight, but is severely weakened and is soon on the verge of being knocked out. A teary-eyed Yazhini, who has found out from Nikita that Peter is not a boxer, tries to convince him to call off the fight, but he refuses. Peter manages to fight back, eventually knocking out "Killer" Peter, causing a major upset. Peter wins the boxing tournament and dedicates the prize money of ₹2,00,00,000 to the astounded IT gang, oblivious to their treachery, but they deny the offer. He also publicly conveys his love to a sobbing Yazhini, who is relieved that he has survived.

The movie ends with a display of a portion of the newspaper the siddhar had materialised torn by Nikita and left at the Chandragiri forest several months ago. The portion shows a photo of Peter lifting the boxing tournament trophy.