At the thana, Inspector Barat greeted us with a smile. “Finished with the account book already?”

Byomkesh replied, “There’s only a year and a half’s worth of accounts in this book—meaning Pranahari started a new ledger after coming here.”

Barat asked, “Did you find anything?”

Byomkesh said, “Nothing that sheds light on the murder. But there’s a small detail that bothers me.”

“What’s the matter?”

“Pranahari had an arrangement with a taxi driver—he would bring him from home every day and drop him back again. Surely there was a monthly payment for this service. But in the ledger, I see the exact opposite. Here, look at the book.” Byomkesh opened the ledger and showed it to me.

On each page, side by side, were columns for credits and expenses. In the expenses column, entries went down to a single paisa or two, but most days the credit column was empty. Occasionally, there was a note of interest deposited by some debtor. Byomkesh pointed with his finger, “Look here, on the 3rd of Magh, under credits, it says: Taxi driver, thirty-five rupees. It’s the same every month. But under expenses, there’s no mention of any payment for the taxi.”

“Perhaps, by mistake, the expense was written in the credit column.”

“Every month, the same mistake?”

“Hm. What do you think?”

“I can’t say. There’s no record here of gambling winnings or losses either. Doesn’t it all seem a bit mysterious to you?”

“It certainly does. What can be done about it?”

Byomkesh thought for a moment and said, “If we could find the taxi driver who used to ferry Pranahari, we could question him. Do you know him?”

Barat replied, “No, I never thought to look for him. Let’s do one thing—let’s send for Bhuban Das. He should be able to help.”

“Bhuban Das?”

“The taxi driver who took those four to Pranahari’s house that night—his name is Bhubaneshwar Das.”

“Oh—can we find him?”

“The taxi stand is nearby. I’ll send for him.”

Fifteen minutes later, Bhubaneshwar Das arrived, saluted, and stood before us. He was of medium build, dressed in khaki trousers and shirt, a cap on his head like a guard’s. Age—about thirty or thirty-two. His eyes were reddish, his face grave. I wondered if the man was under the influence.

Barat nodded at Byomkesh, signaling him to proceed. Byomkesh looked Bhuban Das up and down, then began his questions.

“Your name is Bhuban Das. You were in the military?”

“Yes, sir.”

“A sepoy?”

“No, sir, a truck driver.”

“How long have you been driving a taxi?”

“Three or four years.”

“All three or four years here?”

“No, sir, I’ve been here about a year and a half. Before that, I was in Calcutta.”

“Where is your home?”

“Medinipur district, Bhagabanpur village.”

“You took four people to Pranahari Poddar’s house that day?”

“Not to the house, sir—some distance away from it.”

“All right. While they were in your taxi, did they talk among themselves?”

Bhuban Das hesitated a moment,