A brilliant scientist builds a humanoid robot to protect mankind, but things go awry when human emotions are programmed and inner turmoil causes the robot to act against him.

A man, surrounded by birds, hangs himself to death at a cell tower. Elsewhere, the scientist Vaseegaran introduces Nila, his new humanoid robot, to a group of students. A little later, a student’s smartphone starts flying all on a sudden, exhibiting avian characteristics. Before long, cell phones all over Chennai begin to fly away, leaving the city in chaos. At an emergency council meeting initiated by the government, Vaseegaran enunciates that it is beyond conventional science to fight what he considers a fifth force, and proposes reinstating Chitti, which was dismantled in 2010. But Dhinendra Bohra, who lost his father, Professor Bohra, to Chitti’s anger,[a] opposes, and the council decides to seek help from the military, thereby vetoing Vaseegaran’s proposal.
The growing stream of cell phones leave havoc in its path, killing a mobile phone wholesaler Jayanth Kumar, a transmission tower owner Ranjit Lulla and the state’s telecom minister Vaira Moorthy. To prevent further damage, S. Vijay Kumar, the Home Minister, unofficially gives Vaseegaran permission to rebuild Chitti. Chitti traces the mobile phones, which have taken the form of a giant crow, and they fight, during which Chitti’s battery power is depleted and it starts searching for a power source amongst three huge signal transmitters. To Chitti’s surprise, the crow is unable to penetrate the field of transmitters and suffers damage while attempting to do so.

A disillusioned everyman, frustrated with the corruption he sees all around him, develops multiple personalities in order to restore justice.

The State’s Chief Minister, after being questioned by a reporter, Pugazhendi, challenges him to accept the position for a day, and see for himself the challenges that face him. Pugazhendi accepts the challenge, and immediately sets about to tour the region, suspend and prosecute corrupt officials, arrest several politicians, including the Chief Minister himself, and makes swift and decisive changes that will go to assist the most vulnerable, much to the chagrin of people in power.. After the day is over, Pugazhendi will find his and his loved ones’ lives in danger as the state’s machinery, as well as goons, gather together to extract vengeance.

Two buddies Venkatramakrishnan and Sevalkodi Senthil set out in search of their long lost friend Panchavan Parivendan aka Pari. They have a nerd Srivatsan for company and through intermittent flashbacks we are told that Pari, a bright, yet free-spirited student, who through his charisma is able to convince his two friends to think for themselves, follow their heart and take challenges with a positive attitude chanting his mantra: all is well. Pari wants to change the education system and often lock horns with Professor Virumandi Santhanam the Principal whose says: “Life is a race – Run Run Run”. He wins the heart of Virumandi’s daughter Riya and the film is about his journey.

After a decade of research, the scientist Vaseegaran creates a sophisticated android robot with the help of his assistants, Siva and Ravi, to commission it into the Indian Army. He introduces the robot, named Chitti, at a robotics conference in Chennai. Chitti helps Sana, Vaseegaran’s medical student girlfriend, cheat in her examination, then saves her from being assaulted by a group of thugs. Vaseegaran’s mentor, Professor Bohra, is secretly engaged in a project to create similar android robots for a terrorist organisation, but has so far been unsuccessful.
Vaseegaran prepares Chitti for an evaluation by the Artificial Intelligence Research and Development (AIRD) Institute, which is headed by Bohra. During the evaluation, Chitti attempts to stab Vaseegaran at Bohra’s command, which convinces the evaluation committee that the robot is a liability and cannot be used for military purposes. Vaseegaran’s effort to prove Bohra wrong fails when he deploys Chitti to rescue people from a burning building.

A software engineer comes to India to serve the nation and invest in nation’s welfare. A few corrupt officials and politicians try to stop him but he overcomes all obstacles.

Student in a South Indian college Prabhu is elected as the student leader of the college. When the principal asks him to invite the Governor of the state, Ranjit Singh Rathore, to be the chief guest at the annual day function Prabhu meet up with Ranjit Singh’s daughter, Shruti who happen to be the girl of his dreams. In order to captivate her attention Prabhu join Shruti’s dancing class and is able to impress her thus both fall in love; due to fear of terrorism in the region Shruti is not allow to move without bodyguard. She decides to break this rule in order to run away with Prabhu to a dance festival in Chidambaram only to find life threaten by a bomb that is implanted in that region at that time. But she manages to elude this only to return home whereby her father objects to her relationship with Prabhu and on his behest Prabhu is arrested by the police and accused of planting the bomb in Chidambaram, torture and then later on release. Unknown to the general public Ranjit is involved with a dangerous bomb expert who is responsible for many bomb blasts in the region and Prabhu’s life is under his threat as he has certain evidences that can incarcerate the duo.

Five college boys while away their time by going after girls and getting drunk at parties. However, they are forced to earn a living when one of them gets married against his parents’ wishes.

A veteran freedom fighter named Senapathy learns a rare form of martial art that enables him to kill anyone with his bare hands. He uses that to end crime and punishes the culprits on his own.

In Ooty, Krishnamoorthy alias Kicha (Arjun) and Mani (Goundamani) perform a swashbuckling heist of money of several crores while being in disguise diverting the attention of police, and escape in Nilgiri Mountain Railway, much to the frustration of a chasing police officer Ratnam (Ajay Rathnam). Kicha is a respected citizen who runs a home-based pappadam business along with Mani in Chennai. Susheela (Madhoo), one of Kicha’s many female employees, has a crush on him and is constantly demanding his attention. Another thing adding to her woes is the arrival of her jovial cousin Sugandhi (Subhashri). She makes the place so lively and playful with silly fights between Mani and Babloo (Senthil). Sugandhi later develops a crush on Kicha, especially after being saved by him from some molesting goons. Kicha reveals to her that he has no such feelings for her and wants her to find a suitable mate. Before leaving Chennai, Sugandhi steals Kicha’s ring as a souvenir.

Vishu and Ramu are a pair of Indian twins living in America with their father, Rajamani. When Madhumita (Aishwarya Rai) and her brother come to America to get medical treatment for their ailing grandmother, Vishu and Ramu end up meeting them at the airport. Vishu falls in love with Madhumita, and the couple has everyone’s blessing, except for Rajamani, who is estranged from his own twin brother. He only wants his sons to marry twin sisters, so Madhumita pretends to have a twin in order to please him. As Madhumita puts on a charade by creating Vaishnavi, all goes well, until Ramu falls in love with Vaishnavi. Now the truth must come out, before Madhumita has to marry both of Rajamani’s twin sons.