"PETTA RAP" tells the love journey of BALA (a middle class man whose ambition is to become the best action hero of Tamil movies.) and JANAKI (a local girl, who becomes a Pop Singer.)
Petta Rap is a musical, fun-filled action movie starring Prabhudeva and Vedhika in the lead roles. The film tells the love story of Bala (Prabhudeva) and Janaki, also known as Jeni (Vedhika), in a non-linear narrative. Bala is a junior artist in Tamil movies, aspiring to become a star. He is a die-hard fan of Prabhudeva, having been inspired since childhood when he first saw the film 'Kadhalan' in a theater. Since then, he has tried to emulate Prabhudeva but hasn't succeeded.
Janaki was Bala's classmate in high school. An introverted girl, she fell in love with Bala, the hero of their school. However, Bala ignored Janaki as he was in love with another girl, Kabani. This love failure profoundly affected Janaki's life. As time passed, Janaki transformed into Jeni and became a pop singer, while Bala remained a junior artist.
Jeni and her friend, musician Karthik, have a heated argument in a pub. When Karthik tries to attack her, she swings a beer bottle at him but accidentally hits Rony instead. Rony's brother, Michale, the uncrowned king of the Thoothukudiharbor, learns of the incident and decides to take action. He and his gang follow Jeni in a car. Meanwhile, Bala, the protagonist, is on his way to an audition on his bike when Jeni's car splashes mud on his shirt. At the same time, Michale's car collides with Bala's bike. Angered, Bala confronts Michale and his gang, ultimately overpowering them and leaving them hospitalized.
After these incidents, fights become a regular part of Bala's life. Jeni launches a new music band named 'Queen of Refusal,' and Bala, along with his friends, attends the launch ceremony. During the event, Bala dances with Jeni on stage but doesn't recognize her. Jeni, however, realizes that it is her old crush Bala, though she chooses not to reveal her identity.
Bala gets an opportunity to act as a second hero in a film, but at the location, he gets into a confrontation with the lead actor and ends up being banned from the industry. Realizing that he has become a failure and a disaster, Bala decides to commit suicide. Before doing so, he chooses to live like a hero for a few days. He steals 80 grams of gold from his home and sells it. With the money, he and his three friends embark on a lavish journey.
On the third day of his journey, Bala realizes it might be his last. He finds himself on the shore of a river, contemplating suicide by drowning. However, a final wish arises in his mind: to have a drink of Jack Daniel's whiskey. This wish leads him and his friends, by chance, to Jeni's wedding reception. This unexpected encounter at the wedding transforms both Jeni's and Bala's live.
