Biology teacher Devki is vivacious and popular among her students. At home, however, despite her persistent and warm approach, her stepdaughter Arya remains frosty and distant. Arya is invited to a Valentine-Day party at a farm house; Devki permits this with great hesitation. Arya goes to this party and rebuffs Mohit and his hotshot buddy Charles. Incensed by this very public snub Charles and Mohit and Jagan and the watchman Babu attack Arya when she leaves the party. They violently rape Arya and dump her in a drain. Devki is shattered. Her husband Anand cuts his business trip short and hurries home. Arya recovers and releases a statement naming her attackers.
The case is fast-tracked. Inspector Matthew quickly rounds up the attackers. But the case falls apart. Arya was found to be drinking. The body samples were recovered very late and were too weak to match the attackers. Others at the party provide a strong alibi. The judge acquits. Her lawyer suggests appealing to a higher court but Devki has lost the faith and strength to carry on. Arya, still in shock, tears away from Devki. In deep sorrow Devki realizes that she has probably lost Arya forever.
She recalls the somewhat shady detective DK she had met on the night Arya was raped. A father of a daughter himself, he understands her pain and agrees to help her. She wants information. She wants to avenge Arya.
The watchman is first. Devki seeks the help of her former students, transgender people who deeply understand her plight. They seduce the watchman and drug him. He awakes four days later, still drunk, and finds, to his horror, that he has been castrated and remembers nothing! The hotshot Charles is next. Devki breaks into his home and mixes crushed apple seeds – a source of cyanide – into his fitness powder. Charles is paralyzed. When Mohit visits Charles at the hospital Devki, tipped off by DK, plants apple seeds and other evidence at Mohit’s home and sets off the alarm. Inspector Matthew quickly arrests Mohit; Charles will die soon and Mohit will be the murderer. Matthew finds Devki’s glasses in Mohit’s apartment and now suspects Devki.