Paap is a crime thriller drama. The movie revolves around a young girl Kaaya (Udita Goswami), living in the valley of Spiti, and has a wish to join a Buddhist monastery. A senior lama from the monastery learns that their teacher has been reborn. He sends Kaaya on the mission to bring the child back to the monastery from Delhi. Kaaya leaves for Delhi and finds the child, but things go haywire when the child witnesses a murder. A police officer named Shiven (John Abraham) prohibits Kaaya and the young boy from leaving the city and meanwhile protects them. Kaaya and Shiven grow closer over time. Kaaya is confused with her newly found feelings for Shiven, as for her indulging in sexual activities is sin (paap), but she can’t deny these feelings. Kaaya must maintain celibacy to attain the knowledge of the ultimate truth. Will Kaaya succeed in bringing back the boy to the monastery? Will she subdue her feelings to achieve her ultimate goal?