In the 1950s, a struggling stage actor Anandan (Mohanlal) seeks opportunities to act in films. While waiting for one such opportunity, small-time writer Tamizhselvan (Prakash Raj) comes there and they have a little debate on his satirical poetry, which turns into mutual respect. Anandan requests him to write the dialogues for his audition and Anandan's audition floors the director and he is finalized as the hero. Anandan's friendship with Tamizhselvan grows; Anandan joins Tamizhselvan's political party which is led by Ayya Veluthambi (Nasser). Anandan is forced by his mother to marry a village belle Pushpa (Aishwarya Rai), while Tamizhselvan marries a village girl (Revathy) as ordered by his party leader.
On returning to Madras, Anandan learns that his film is cancelled due to financial difficulties and he sends Pushpa back to her village. During a film shoot, Anandan is informed by his mother that Pushpa died in a freak accident. Tamizhselvan consoles the grief-stricken Anandan.
A few days later, Anandan's assistant (Delhi Ganesh) invites Anandan for an audition. Anandan invites Tamizhselvan, who leaves his wife in labour pain, to support Anandan at that critical time. He writes dialogues for Anandan again and the movie starts rolling. Anandan is paired with actress Ramani (Gauthami); the film becomes a huge success. While shooting the next venture, Anandan and Ramani have a romantic tryst and her lusting uncle ('Nizhalgal' Ravi), assaults her. Ramani seeks Anandan's protection, and Anandan marries her.
Anandan becomes a successful hero; encouraged by Veluthambi, his stature in the party grows. During party meetings, the crowd responds most to Anandan, which disturbs even Tamizhselvan.
During the crucial State Assembly elections, Anandan is shot by a fellow actor. Everyone suspects this to be the Opposition's work. The photograph of an injured Anandan is displayed across the State; Veluthambi's party and Tamizhselvan win the elections.
Disappointing everybody, Veluthambi chooses to be a guide and asks the party to elect a new Chief Minister (CM). Everyone recommends Madhuvannan (Rajesh) a senior party leader. Tamizhselvan seeks Anandan's support which tilts the balance and Tamizhselvan becomes the CM.
Anandan expects a post in the Ministry, but Tamizhselvan tells him to first quit films. Anandan does not accept and walks out. Anandan's aides instigate him against Tamizhselvan and he starts doubting Tamizhselvan's intentions.
Tamizhselvan has an affair with a literature-lover Senthamarai (Tabu) and soon marries her. Anandan calls for auditions for a new heroine. Newcomer Kalpana (Aishwarya Rai again), who resembles his late wife Pushpa, is recommended by all, making Anandan uncomfortable. While working together, Anandan mentions her resemblance to his late wife Pushpa, which sparks off an affair between them.
At this juncture, Veluthambi, who had kept Anandan and Tamizhselvan together in the party, dies. In the condolence meeting, Anandan creates a controversy by demanding that all party members must declare details of their assets to the public which prompts Tamizhselvan to sack Anandan from the party.
Anandan retaliates by forming his own party. Work keeps him away from Kalpana and she walks out. Anandan's star power and ability to spread social propaganda through his films enables him to win the ensuing election and become the CM.
Madhuvannan joins Anandan, confident that Anandan's reign will see less dirty politics. This sparks off Tamizhselvan and Anandan to devise tactics to outdo each other. Madhuvannan realizes that Anandan's reign is no different from Tamizhselvan's. After a while, Anandan meets Kalpana again and sends his assistant (Delhi Ganesh) to bring her back. While returning in the car Kalpana, Anandan's assistant and his driver die in an accident.
After this accident, a distraught Anandan loses interest in life. Tamizhselvan, released from jail, also slows down his political tactics as age catches up with both. At a wedding function, Anandan and Tamizhselvan meet and graciously shake hands. The wedding is in the same venue where they first met, prompting memories and smiles from both. As the wedding concludes, Anandan loses his footing and falls. The next morning, Ramani tries to wake up Anandan but realizes he has died in his sleep.
Shocked to learn of Anandan's death, Tamizhselvan rushes to see him but is unable to see the body. Realizing that the people will always assume him to be Anandan's enemy, he returns to the place where they first met. In an emotional monologue, he recites poetry mourning his friend's death, which displays the depth of their friendship. The film ends with Anandan's body being paraded through the streets, mourned by a legion of film fans and politicians.
[from the book Pride of Tamil Cinema: 1931 to 2013, by G Dhananjayan, Blue Ocean Publishers, 2014]