The story involves a talented Bengali scientist specializing in biochemistry (Nihar Ranjan Dutta) who conducts cancer research in America. He has a treachorous Bengali assistant (Suprakash Choudhury). Due to Choudhury's treachery Dutta becomes blind and comes back to Kolkata without completing his research.
Many years later, during an evening when Feluda visits Dutta's home to investigate the previous night's burglary attempt, Feluda suddenly discovers that Mr. Dutta's research paper and a handful sum of cash money have been stolen. Feluda starts investigation and he is introduced to Ranjit Bandopadhay (Dutta's secretary) and Dutta's two tenants Sukhwani and Dastoor. Feluda returns home. On the same night, Dastoor is murdered.
Feluda starts investigation and finds that Dutta's research paper and money were stolen by Mr Ranjit Bandopadhyay. He stole the research paper to get fame by conducting research with the help of those paper. Feluda also knows that Dastoor was actually disguised Suprakash Choudhury who stayed in Dutta's home to steal those research paper. Dastoor was murdered by none other than Mr. Nihar Ranjan Dutta to take revenge. But Feluda did not take any action against Mr Dutta because he was old and also it seemed that Feluda had sympathy to the motive behind the murder.