Nupur Chatterji has fled from her home in Delhi, resisting an arranged marriage with a man she dislikes. She comes to Calcutta to her college friend, but as her home is not safe she takes shelter in the house of one Anjan Mukherjee. Though initially annoyed, Anjan, a bachelor and a music director cum singer from Lucknow, comes to empathise with Nupur. In this situation enters the great detective Bhanu with Jahar, his assistant, for by now Dr. Digambar Chatterji has declared a prize money of ten thousand rupees for finding his missing daughter.
