Calcutta, soon after the Second World War. Summer was at its peak. Satyaboti’s brother, Sukumar, had taken her and the child away to Darjeeling. Byomkesh and I were on our own in the Harrison Road flat, left to roast in the heat.

Work was a little slow for Byomkesh just then. This was nothing new; but this time, the length of the slack period and the sheer monotony of leisure were getting on our nerves. We were urgently in need of some diversion. To compound our misery, Satyaboti and the baby too were away. In sheer desperation, we had taken to playing chess.

I had an aptitude of sorts at the game and I had taught it to Byomkesh. At the outset, he was quite easy to trump. But with time, it became increasingly difficult to beat him at the game. Eventually, the day arrived when he checkmated me with the unexpected move of a pawn. I was aware of the saying that there is no shame in being defeated by one’s disciple. But when you start losing to someone whom you have only just initiated into the game, you begin to lose faith in your own abilities. I was quite disconsolate.

It didn’t help at all that it was unbearably hot. Ever since that morning in March when I had woken up with my bed soaked in sweat, the last month and a half had seen a gradual rise of the mercury with no respite in sight. It was not as if it didn’t rain a couple of times, but this only served to step up the humidity level. The fan whirred overhead relentlessly, night and day, but this brought no relief either. I felt as if I were immersed from head to toe in rasgulla syrup.

With mind and body in this despondent state, we had set the chessmen out on the charpoy again one morning. Byomkesh was on the verge of checkmating me with his rook and I was perspiring profusely from the anxiety his anticipated move generated when there was an intrusion.

It came in the form of a soft but persistent knocking on the door. It couldn’t be the postman—his knock carried a note of aggression. So who could it be? We looked at one another in eager anticipation. Could it be that the long-awaited new mystery crying for a solution had come to our door at last?

Quickly, Byomkesh slipped on a kurta and opened the door. Meanwhile, I too made myself decent for company by draping a thin muslin stole over my naked torso.

The door opened to reveal a middle-aged gentleman. He was of medium build, a little stolid, with a sharp, clean-shaven face. On his nose sat a pair of frameless spectacles with tinted lenses. He had on a pair of snow-white trousers and a half-sleeved silk shirt. He wore no socks, but was shod in a pair of braided, Grecian sandals. All in all, a well-turned-out look.

In a very