Thamma is a romantic horror comedy that revolves around Alok Goyal (Ayushmann Khurrana), a small-town TV reporter who lives with his parents (Paresh Rawal and Geeta Agarwal) and faces his father’s taunts for not doing anything worthwhile in life. One day Alok goes on a trekking trip in the hills with his friends where he is unexpectedly attacked by a bear that leads him to Tadaka (Rashmika Mandanna), a mysterious woman who saves and heals him. Alok is attracted towards Tadaka but soon life takes a u-turn for him when he is soon captured by a strange tribe led by Yakshasan (Nawazuddin Siddiqui). Tadaka defies her clan to save him, sparking a chain of events that threaten her world and his. What happens next forms the rest of the film.