For a couple of days afterwards Byomkesh didn’t bring this case up at all. I could guess at his state of mind, so I didn’t urge him either. On the evening of the third day he started speaking of his own volition. Haphazardly, talking almost to himself, he began, ‘There is a phrase in English—vengeance coming home to roost—that is what happened to Debkumarbabu! He had wanted to kill his wife, but such was the will of fate that both times he aimed his lethal arrows, they struck his son and daughter, who were dearer than life to him.

‘Quite unexpectedly, Debkumarbabu had come upon an extraordinary invention. But due to a lack of funds, he was unable to make proper use of it. With an invention such as this, you cannot apply for a patent, because it has no value in the commercial market. But if war-prone, expansionist nations like Germany, Japan or France ever got wind of the formula, they would immediately start producing this lethal poison in their laboratories. The inventor wouldn’t be able to do a thing and he wouldn’t stand to gain anything out of his invention.

‘So Debkumarbabu kept it all under wraps. He needed funds badly because much experimentation was needed to find out all the uses of the poison. But where was the money? In order to conduct such a huge experiment in complete secrecy, he would need his own laboratory, and that requires massive resources. Where would so much money come from?

‘Meanwhile, at home, Debkumarbabu’s wife was making his life quite miserable. Those who are involved in rigorous cerebral activities require some peace on the domestic front— but this was completely lacking in his life. The company of his finicky, unsympathetic and prattling wife was driving him around the bend. Debkumarbabu is not a violent person by nature. If he was given a peaceful atmosphere in which he could pursue his scientific activities, he would want nothing else. From the love he bore for his children, one can imagine that he has a very caring nature. His second wife, had she tried, could have also received her share of his affection. But she was made in a different mould. In fact, Debkumarbabu had begun to hate the very sight of her.

‘A man does not usually have a desire to kill his wife; when he is driven to this extreme, it is because he has reached the end of his tether. Debkumarbabu too had come to a breaking point. Then the deadly poison came into his possession. Here was a way of disposing of his wife. Deep in the recesses of his mind, he began to hatch a plot.

‘Then he saw the advertisement put out by the insurance company for joint life-insurance policies—the husband and wife could take out the policy together and when one of them died, the other one would get the money. Now all his doubts were resolved. Where would he get such an opportunity again?