Summary Calcutta, 1963. Dr Suresh (Athar Qureishi) visits Byomkesh & begs him to visit his stroke patient who is paralyzed on one side of the body. The patient's name is Bishupal (Sadhu Meher) & is a rich moneylender. Abhay Ghoshal (Suneel Sinha) has borrowed money from Bishupal. But Abhay is a crook. Abhay threatened to kill Bishu if he asked for the money back & that led to Bishu's stroke 3 months ago.

Byomkesh meets Bishu, who says that he knew Abhay's father who was a rich & respected man in Calcutta. He died 2 years ago, which is when he met Abhay. Bishu had heard a few rumors about Abhay, but felt that new money always spoils young minds, before they self-correct. Bishu has a money landing business and has lent Rs 20 L in the market, overall. Abhay approached Bishu for Rs 30,000 to fight a court case 2 years ago. Bishu loaned that amount without a guarantee & now regrets the same. Bishu followed Abhay's legal battles & figures that he was a womanizer. He had trapped a nubile young girl & had a relationship with her & then killed her with poison. That is what the court case was about. He had also squandered his father's property completely.

Bishu got worried about his loan & met Abhay for the collection. But Abhay looked at Bishu like the devil & sent him away. The same night Bishu had a stroke. Since then, Bishu is convinced that Abhay will kill Bishu. Bishu has taken security guard protection & meets no-one except the doctor. There are 2 guards: 8 am to 8 pm and 10 pm to 8 am. from 8 pm to 10 pm the doctor is in the house with Bishu.

Byomkesh meets Abhay & finds that Abhay has no knowledge of Bishu's paralysis. Abhay also denies threatening Bishu or refusing to pay his money. He also suspects that someone followed him to Abhay's house. Only Dr Suresh knew that they were coming to meet Abhay.

The following day Byomkesh finds that Abhay was found dead the previous night after 9 pm. The police tell Byomkesh that Abhay was a known womanizer & had destroyed life of countless women. He had killed his last wife with poison, but his crime could not be proved in court. Byomkesh suspects that Bishu is not paralyzed and is somehow involved in the murder.

Byomkesh gets a police doctor to examine Bishu, who confirms that Bishu is indeed paralyzed. Byomkesh talks to Dr Aseem Sen to understand what medicines can induce paralysis. Byomkesh reveals that Dr Suresh was artificially giving a medicine to Bishu to induce temporary paralysis. This medicine would induce paralysis for 3-4 hours at a time. Bishu was convinced that Abhay wanted to kill him. So, he planned this whole charade to kill Abhay & to recover his money by selling his last remaining property. He involved Suresh in his plan. He also got guards so that they could keep surprise visitors at bay & he could move freely inside his home, without his secret being exposed. Bishu had involved Byomkesh with the confidence that Byomkesh would become a staunch ally and witness and no-one would doubt Bishu. Bishu asked Dr Suresh to keep an eye on Byomkesh, as he met Abhay. Bishu took advantage of the guard's absence from 8 pm and 10 pm to exit the house, murder Abay & come back undetected.

Ajit argues that Bishu killed Abhay in self-defense & law is lenient for that. But Byomkesh reckons that Bishu planned this murder for months & hence cannot be considered in category of self-defense. He informs the police & Bishu is arrested.

• Adventure
• Crime
• Mystery
• Thriller