I was about to ask Lalmohan Babu if he had remembered to bring his weapon and, if so, when would he show it to us, when he spoke unexpectedly.

‘We forgot one thing,’ he said, ‘betel-nuts. We must check with the fellow from the dining car if they have any. If not, we shall have to buy some at the next station. There’s just one left in this little box.’

Lalmohan Babu took out the Kodak container, the only original object left from Dhameeja’s attaché case, and tilted it on his palm. The betel-nut did not slip out.

‘How annoying!’ he exclaimed. ‘I can see it, but it won’t come out!’ He began to shake the container vigorously, showering strong words on the obstinate piece of betel-nut, but it refused to budge.

‘Give it to me!’ said Feluda and leapt down from the upper berth, snatching the container from Lalmohan Babu’s hand. Lalmohan Babu could only stare at him, completely taken aback.

Feluda slipped his little finger into the box and pushed at the small object, using a little force. It now came out like an obedient child. Feluda sniffed a couple of times and said, ‘Araldite. Someone used Araldite on this piece of betel-nut. I wonder why—? Topshe, shut the door.’ There were footsteps outside in the corridor. I did shut the door, but not before I had caught a glimpse of the man who went past our compartment. It was the same old man we had seen at the Jantar Mantar. He was still wearing the dark glasses and his ears were still plugged with cotton wool.

‘Sh-h-h-h,’ Feluda whistled.

He was gazing steadily at the little betel-nut that lay on his palm, I went forward for a closer look. It was clear that it was not a betel-nut at all. Some other object had been painted brown to camouflage it.

‘I should have guessed,’ said Feluda softly. ‘I should have known a long time ago. Oh, what a fool I have been, Topshe!’

Feluda now lifted one of the glasses from its ring, poured a little water from our flask and dipped the betel-nut in it. The water began to turn a light brown as he gently rubbed the object. Then he wiped it with a handkerchief and put it back on his palm.

The betel-nut had disappeared. In its place was a beautifully cut, brilliant stone. From the way it glittered even in our semi-dark compartment, I could tell it was a diamond. And it was pretty obvious that none of us had seen such a large one ever before. At least, Lalmohan Babu made no bones about it.

‘Is that …’ he gasped, ‘a d-di-di …?’

Feluda closed his fist around the stone, went over to the door to lock it, then came back and said, ‘We’ve already had warnings threatening our lives. Why are you talking of dying?’

‘No, no, not d-dying. I mean, is that a diam-m-m-?’