Ambar Sen Antordhan Rahasyo (1999)

Ambar Sen a well educated, intelligent man with a good depth of knowledge on different subjects came to Feluda for a case and gave him a letter on which someone or any group threatened Amber babu a few days ago. The very next day Ambar Sen was vanished. Ambuj Sen the only brother of Ambar babu called Feluda for the case. Feluda, Tposey and Jotayu came to Palm Avenue's Sen House to solve the case. After a long investigation Feluda came back to his house. The very next day Ambuj babu came to Feluda's house with the information that someone called him and asked for one lakh rupees for the release of Ambar sen. The amount was paid and Ambar Sen came back to his house, but Feluda proved that everything was just preplanned and Ambar Sen made all these drama to check Feluda's ability and efficiency.