Set in the scenic town of Tirupathi, 35-Chinna Katha Kaadu tells the story of Saraswathi (Nivetha Thomas), a happy middle-class woman who lives peacefully with her husband, Satya Prasad (Vishwadev Rachakonda), and their two sons, Arun (Arundev Pothula) and Varun (Abhay Shankar). However, their peace is disturbed when Arun starts having trouble with mathematics. He asks unusual questions about the subject, and his strict Maths teacher, Chanakya Varma (Priyadarshi), judges students based only on their grades. Upset by Arun’s poor performance, Chanakya calls him “zero,” which worries his parents. Saraswathi decides to help her son improve his math skills. Will she succeed? What is Arun really thinking? And does Chanakya end up helping Arun? The film answers these questions.