Chitra (Nayantara), a medical student and her friends are working on a project about the human brain. She wants to investigate the curious case of Sanjay Ramaswamy (Suriya), a (former) notable Chennai based businessman, who is reported to have anterograde amnesia. Her professor denies access to Sanjay’s records as it is currently under criminal investigation. Chitra, nonetheless, decides to investigate the matter herself.
Sanjay is introduced as he brutally murders a man. He takes an instant picture of the man, and writes on it “done”. Sanjay has anterograde amnesia; he loses his memory every 15 minutes. Sanjay uses a system of photographs, notes, and tattoos on his body to recover his memory after each cycle.

A mysterious man along with a young computer hacker tries to unveil a major government conspiracy which resulted in several bloody deaths.

Bhaskaran, a college dropout, along with his friend Nallathambi starts a coaching class for students in order to win the love of a young professor, Chandrika.

The movie starts in 1970s, where there is heavy drought in southern districts of Tamil Nadu. Ayyadurai (Sarath Kumar) and Maadasaamy (Napoleon) are close friends and landlords of different castes in Tenkasi town in Tirunelveli district, and they try hard to help people and save them from dying during the drought. Local MLA (OAK Sundar), also a relative of Madasami, smuggles rice given by the government and people protest, knowing about this. The MLA denies knowing anything about the sanctioned rice. That night, he starts to smuggle the rice, but the lorries are waylaid and ransacked by the people led by Madasamy. The MLA comes there and starts shooting towards people’s legs. Ayyadurai sees the MLA aiming for Madasamy’s head and pushes him. Then Ayyadurai beats the MLA using hilt of the gun, following which he dies. But the local people support Ayyadurai and save him from police and also urge him to contest in the assembly by-elections.

“Blade” Ganesh (Jiiva) is a henchman for a local villain Naaga (Sharath Lohitashwa) and is loyal to him. Vithya (Nayanthara) is the daughter of a local factory owner (Joe Malloori). She falls for Ganesh after he saves her from a kidnapping. Vithya’s father arranges for her to marry another man, but everyone learns about the love affair between Vithya and Ganesh, which creates animosity between Naaga and Vithya’s father. Blade gets caught between supporting Vithya’s father and standing up to Naaga. Blade saves the day by killing Naaga.

The film portray the life of a happy-go-lucky-youth named Shiva (Silambarasan), and the different women he meets in his life. All hell breaks loose when Shiva’s equation with his fiancee goes for a toss. What causes friction between the couple? Does Shiva unite with the love of his life?

A village ruffian, who settles disputes in his native, takes on a big shot when he tries to sort out the rough patch in his marriage after several years.

A NRI Anamika (Nayanthara) comes to Hyderabad in search of her husband Ajay Sasthri (Harshavardhan Rane), who has gone missing. She lodges a police complaint in a station which is the nearest to the hotel where he was staying. A sympathetic cop (Vaibhav) tries to help her, while his superior cop who seems to know the truth is lusting after her. Meanwhile, she stirs the state administration with her resolve to find her missing husband, and is thwarted by a cunning state minister (Naresh) and the intelligence chief (Pasupathy). Does Anamika fulfill her mission?

The underworld don Billa (Ajith Kumar), featured on Interpol’s criminal list, is hiding and operating out of Malaysia. DSP Jayaprakash (Prabhu) has spent the last few years looking for Billa, leaving behind a life in India.
During a chase with the police, Billa is severely wounded after an accident and dies in front of the DSP. The DSP then secretly holds a burial of Billa. Interpol officer Gokulnath (Rahman) is assigned to work with DSP Jayaprakash to capture elusive Billa as no-one knows of Billa’s death. DSP Jayaprakash keeps the death of Billa as a secret even from his fellow officers, and tracks down a look-alike called Saravana Velu (Ajith Kumar), a lowly pick-pocket. He asks Velu to infiltrate Billa’s gang by pretending to be Billa. In return he will make sure that the child Velu adopted, Karan, gets a proper education.