Such an intimate examination of the body of their senior officer must have been unbearably stressful for the Afghans, Joe thought, but so extreme were the circumstances of the man’s death and so acute the need to know the truth, they watched on, silent and wary. And the whole thing was only possible thanks to the impersonal, efficient and thoroughly scientific procedure Grace was demonstrating.

Finally, a gruelling hour later, she was ready to sum up. Pointing to a white china dish which held a sample of the vomit taken from the mouth and throat she said, ‘Well, there you have it. The matter expelled consists, as you might expect, of semi-digested particles of the food Zeman ate at the banquet, poultry, rice, fruit and so on. I see no evidence of foreign matter but lacking the facilities of a chemistry laboratory that is as much as I am able to say. The state of digestion, as you see from the size of the particles, is not very advanced and this gives us an indication of the time of death. A time which is borne out, I may say, by the temperature of the body and the progress of rigor.’

‘But why Zeman?’ Iskander interrupted. ‘We all ate the food. No one else has been affected!’

James and Grace looked at each other in horror and each said, ‘Oh, my God!’

‘What? What are you saying? Who…?’ said Iskander.

‘She’s all right, Grace,’ James burst out, grasping her hand. ‘When I left her this morning she was sleeping like a baby and just as pink. She’s all right!’

‘I think you’d better tell us what happened in the night, Grace,’ said Joe. Turning to Iskander he said, ‘I think you should know. I heard a noise at three o’clock and woke. When I looked into the corridor Grace was going along to attend to Mrs Lindsay.’

‘James fetched me. And yes, it would have been at about three. I – we both – assumed it was a return of the sickness she’s been suffering from lately, aggravated, no doubt, by the unaccustomed rich food. She told me she had a stomach pain, had vomited and she had a high temperature. I gave her some drops of Chlorodyne and she began to feel better. I sat with her for half an hour and she fell comfortably asleep so I went back to my room.’

Echoing everyone’s alarm, James said, ‘Look, I’m going to send a bearer to knock up everyone who was at dinner last evening and check whether they’ve been ill in the night. Who’s left? That’s Fred, Burroughs and Rathmore. Lily, as we saw for ourselves, is unscathed.’

He gave orders to a Scout standing in attendance.

‘While we’re waiting… is there any other aspect we haven’t covered? Any other possible cause of this sickness? I’m trying to avoid saying the dreaded word… ’

‘It’s not cholera. No,’ said Grace firmly. ‘Nor yet dysentery. But you’re right. We’ve been concentrating on the internal workings. A poisonous bite perhaps from animal or reptile? As you all saw, there were no puncture marks on his body. A crack on the head will sometimes make you vomit, though perhaps not so… um… copiously. No sign of blood anywhere.’ She had already taken off Zeman’s turban and inspected his head but now she pushed her fingers gently into the thick black hair and palpated the skull inch by inch. With her fingers just beyond the right temple she stopped. She moved them slowly over the interesting patch again and sighed., ‘There it is! Nearly missed it. There’s an indentation. Three inches long and dead straight. Would you like to feel this, Iskander?’

He nodded and allowed her to guide his finger to the spot. He nodded again. ‘As you say,’ he confirmed.

The tension in the room was growing. The Afghan soldiers muttered to each other.

‘A crack on the head! That’s all we need!’ Joe thought desperately. ‘The Amir’s bloody cousin, son of the local Afridi bad boy, killed in suspicious circumstances while he’s under James’s roof, protected by the shield of melmastia. Killed by one of us! We’ll never get out of this alive! Grace, couldn’t you have kept your mouth shut?’

But Grace now had the bit between her teeth, the complete professional, absorbed in her task and, watched intently, she was busily shaving away the hair from the suspected wound. ‘There!’ she announced with satisfaction. ‘No wonder I didn’t spot it. No bleeding, you see, and very little distortion.’

‘It’s very straight,’ Iskander commented, his eyes watchful like a stalking cat.

‘Yes, isn’t it?’ said Grace apparently unconcerned. ‘As the skin has not been penetrated to any depth it was obviously not a blow from a talwar or sharp blade of any kind. The skull has not been crushed so it’s not a rifle butt or any of the blunt offensive weapons I expect you come across every day in your work, Commander.’

Joe caught the edge of something in Grace’s tone. She was appealing to him in some way. ‘The poor old girl’s probably feeling the strain of all this, though she hides it well,’ he thought. ‘It’s been a one woman show so far and she’s done it beautifully but she needs some help.’

‘You’re right, Doctor. Not the blow of someone attempting to kill him, you’d say. Just one blow and such an unlikely wound formation,’ he said. ‘In my experience of head wounds battering occurs. You find several blows on different parts of the skull delivered in uncontrollable rage or to make absolutely certain. And there are no defensive wounds visible, are there? I mean injuries to the hands and arms which a victim receives in his attempts to ward off the attack.’ He looked again carefully at Zeman’s hands and lower arms. ‘No scratches. Not even a broken nail.’ And then, ‘Good Lord! I know what this is! Iskander – Zeman was lying slightly on one side when we found him, wasn’t he? Which side? Do you remember?’

Iskander was ahead of him and broke in, ‘It was the right side. Like this.’ He demonstrated the position. ‘And Zeman’s head was resting across the step… like this. Are you saying, Sandilands, that he collapsed on the stairs and cracked his head on the straight edge? They are stone, those steps, are they not?’

‘They are, and very sharp-edged! I barked my shin on one while we were carrying the body around earlier. There you are!’ He rolled up his trouser leg and revealed a livid bruise across his shin. ‘Same sort of injury.’

‘Mmm… that has to be speculation though. Let’s take a closer look, shall we?’ said Grace.

Wretched woman! Did she never know when to stop? Joe wondered.

Taking a magnifying glass from her kit she peered over the wound, grunted, smiled with grim satisfaction, reached for a pair of tweezers and plucked out something invisible to everyone standing by.

Iskander knew what was required of him.

‘They’re doing a bloody double act,’ Joe thought. ‘What is going on?’

Iskander took the magnifying glass and held it over the end of the tweezers. He breathed out a gusty sigh. Of relief?

‘A flake of white stone,’ he announced solemnly.

The Afghanis queued up to examine it in turn, each sighing and nodding.

‘So,’ said Iskander with authority, ‘we are evidently looking at a death by natural causes. Zeman eats something infected at supper, leaves it late before he attempts to seek help, dies on the stairs and hits his head as he falls.’

One of the other Afghanis said something hesitantly and Iskander nodded gravely. ‘My friend is asking, Dr Holbrook, what are the possibilities that Zeman was poisoned? Poisoned deliberately?’

Again in two languages Grace began, ‘It is certainly possible. Even likely. For this reason we must gather together all who were at the evening meal and find whether anyone else has been affected. We must establish the course of the meal, exactly what he ate and drank. James, could we meet at once in the library? No – back in the durbar hall – it may help people to remember more clearly. It would be a good idea to have last night’s kitchen staff standing by in case we need to speak to them. And, Iskander, I would like your officers to be present at our deliberations.’