On an invitation by Mahitosh Singha Ray, Lalmohon Babu takes Feluda and Topshe to a forest near Bhutan and stays at the ancestral home of Mahitosh Singha Ray. After few days of their arrival,Mahitosh Singha Ray's assistant, Tarit dies. His deadbody is found in the forest, and police believes he has died due to a tiger's attack. But later they found a blood-stained sword near his body. Meanwhile, Mahitosh gives Feluda a riddle to solve. Feluda's amazing intelligence is proved in this part. He solves it most amazingly, and at the end, chalks out that a treasure chest is hidden 55 hands away from a tree which has a hole between it, which looks like an old person's mouth without any teeth; between two Arjuna trees. While Feluda and his companion are on the way to the treasure chest, they finds Tarit's spectacles and later on, his torch, which suggests that Tarit has solved the puzzle much earlier than the others, and was on his way to the treasure chest. At last, Feluda finds the treasure chest, and helds out the conclusion. Mahitosh had broke his hand due to a fall from a tree, which Feluda came to know when he was unable to hold the rifle. All the precious huntings of the tiger were done by his friend, Shashanka. On that night, while Tarit was about to leave, Shashanka too followed him quietly. When there came a Royal Bengal Tiger. Shashanka fired his rifle, which shoot off the tiger's nose after Feluda found a bit of skin. Tarit's sword, as he observed, has begun acting like a magnet, which was started by a bolt of lightning striking it. Thus, Tarit wasn't murdered by any villain, but only, nature was the cause of his death. He, at the end of the story is rewarded with a part of treasure.