In Mysore, a woman named Neela is harassed by a man in a bus; commuting to her workplace. Neela arrives home and tells about this to her grandmother Raama, a retired Inspector. Raama advises her to read a book titled Vedha, which revolves around a hooligan-turned vigilante named Vedha.
In 1980s, Vedha meets his daughter Kanaka, who is released from prison, and the duo set on a killing spree. They wander from one village and kill three persons: Inspector Rudra, Giri, Nanjappa. Vedha also rescues two women from being sold as bonded labourers and punishes those people responsible. Ramaa took charge as the Inspector, and along with constable Govindappa, begins to investigates the incidents and deduces that Vedha and Kanaka are responsible. From a lawyer named Girija, Ramaa learns about Vedha’s past.
Past: Vedha leads a happy life with his wife Pushpa and daughter Kanaka. Later, Vedha is sent to prison for three days for a theft committed by Beera. One night in a drunken state, Giri, Beera, Kalaiyan and Nanjappa brutally assault Kanaka. Enraged by this, Pushpa attacks them only to get killed by them. Rudra also helps them to destroy the evidence, and gets Kanaka sent to juvenile prison. After learning this, Vedha kills the witness Chowdappa for false testimony; attacks Rudra (who survives later) and absconds from the village, waiting for Kanaka to get released from prison and exact vengeance.
Present: Vedha and Kanaka arrive to kill Kalaiyan, who later commits suicide out of guilt. They also arrive at Beera’s house and decapitates Beera’s wife, and later kills Beera. Ramaa arrives, along with Paari, a sex worker, and Vedha’s friend Daya. Paari reveals that Daya was also involved in Kanaka’s assault, and he was the one who informed his location to Beera. Paari also had tried to kill Daya many times, but the latter always managed to escape. Vedha gets enraged and kills Daya, thus avenging the injustice committed against Pushpa and Kanaka. Later, Vedha and Kanaka immerse Pushpa’s ashes into the river, and continues their vigilante activities.
After listening to Vedha’s story, Neela finally gains newfound courage and heads back to work. While heading to her workplace, Neela gets harassed again by the same man in the bus, only for her to stab his penis with a ball pen.