Colonel Danilov entered first, then Dr Tarasov, and finally Dr Wylie. Each looked upon the tsar with his own brand of affection and his own veneer of pity. But, to a man, their faces were grave. They were clever men; the tsar knew that. It was flattering to have his conclusion endorsed by such minds as theirs.

Aleksei breathed deeply as he left the tsar’s bedchamber. Prince Volkonsky had been hovering outside. He looked at Aleksei enquiringly. Aleksei shook his head briefly and the prince’s face fell. Baron Diebich looked from Volkonsky to Aleksei and back. There could be no mistaking the news.

Wylie and Tarasov came out of the room a moment later. Their faces showed the same gloom as Aleksei’s.

‘Is there no hope?’ asked Volkonsky.

‘There is only hope,’ replied Wylie.

‘He seemed so much better,’ said Diebich, as if the assertion would change things.

‘A flicker of life,’ Wylie told him. ‘I have witnessed it in more than one case. The will of the patient can be strong enough to overcome all symptoms, but only briefly.’

‘How long does he have?’ asked Volkonsky.

‘Days – perhaps hours.’

‘The poor tsaritsa,’ muttered Diebich.

‘He has asked to speak with you,’ said Tarasov, addressing Volkonsky. Diebich half rose to his feet, but Tarasov raised a hand to him. ‘Only the prince, I’m afraid, Baron – for the time being.’

Diebich nodded and pressed his lips together hard. Volkonsky went into the tsar’s room. Aleksei took another deep breath. There were still matters to be discussed with the doctors. Diebich was slumped mournfully in a chair beside his master’s door. Aleksei glanced at first Tarasov and then Wylie, nodding towards the door that led out to the garden, before heading through it.

Neither of the doctors was cut out to be a spy. They appreciated the fundamentals – that if three men intended to meet for a private conversation, then it was wise for them not all to head off to it at the same time – but the execution of their seemingly casual departures from the house was excessively theatrical, and the timing of the separation between their exits too precise. It did not matter. No one would be concerned that three of the tsar’s staff were talking at this time – however much they might be curious about the role of an interloper such as Aleksei. In their grief, no one in the house would be up to observing anything much.

‘You think His Majesty will be able to convince Volkonsky?’ asked Aleksei.

‘He has to,’ said Tarasov. ‘The prince is far too sharp not to spot what’s going on – and to stop it. He has to know that what we are planning is, ultimately, in the tsar’s best interests.’

‘And His Majesty is the only person who can convince Volkonsky of that,’ added Wylie.

‘The prince will think he’s delirious,’ said Aleksei. ‘We should have stayed to add the weight of our voices.’

‘If Volkonsky wants our opinions, he will seek them,’ insisted Tarasov. ‘Those two have known each other a long time – in the end, Volkonsky will obey. And the tsar is not going to tell him everything.’

‘I suppose you’re right,’ conceded Aleksei. ‘But we do need Volkonsky. Security is vital.’

‘You’re sure Cain will come?’ asked Wylie.

‘He must. There’s nothing he can do once His Majesty is dead, and so he will try to find a way to administer a further dose of Zmyeevich’s blood. Then – if I were him – I’d also make sure of the tsar’s death. It would be foolish to leave anything to chance.’

‘We should be grateful you’re not him,’ said Wylie.

‘Are we really certain that the effects of the first taste of the blood have passed?’ asked Tarasov.

‘We can’t know for sure,’ said Aleksei, ‘but I’m convinced Cain thinks they are. That is why he will come.’

‘And we’ll be ready for him,’ said Tarasov.

‘You two will be attending the tsar,’ replied Aleksei. ‘Volkonsky will arrange a guard around the palace. I’ll make sure he puts me in charge of them.’

‘From all we’ve seen, Cain’s a dangerous man.’

‘That’s why they’ll have orders to kill,’ said Aleksei. That, and other, more personal reasons.

‘If only we could do more,’ said Wylie.

‘You can do the most important thing of all,’ insisted Aleksei. ‘You must both make sure that His Majesty eats and drinks nothing in the hours leading up to his death – otherwise everything else we do will be a waste of time.’

Aleksei walked away from them briskly and strode back towards the house. He had seen that Volkonsky was beckoning to him.

The tsaritsa was more desperate than the starets had ever seen her. She had heard from Father Fyodotov – and other gossips in the royal household – how grave her husband’s condition was. Fyodotov seemed to know more, but his lips were closed by the seal of confession. The starets wondered how much Aleksandr had told him.

She had come to the monastery again to speak to him – at his summons, though he felt certain she would have sought him out anyway.

‘He is dying, Father,’ she said after they had recited the Prayer of the Heart.

‘Has he made his confession?’ It was better for the starets not to reveal the conversations he had had with Fyodotov.

‘Yes. And then it seemed he had got better, but it was only a passing rally. He might die within hours, the doctors say.’

The starets leaned forward. This was surprising news. ‘As soon as that?’ he asked.

‘I should be with him, Father. But you are my only hope.’

‘Jesus Christ is the hope of the world,’ said the starets. ‘I am merely His representative on Earth.’

‘Please, Father – there is so little time. Do you have the remedy you promised me?’

The starets might have taken time to lecture the tsaritsa on the virtue of patience, but from what she had said, he knew that time was now pressing. For the tsar to die now would be intolerable. He slipped his hand into his robe and brought out a small vial. He handed it to the tsaritsa. She took it from him and grasped it to her chest. A flood of hope ran across her face, and yet still she doubted.

‘So little?’ she said.

‘So little your faith?’ he replied. ‘That is all that is needed.’

She nodded and looked down at the thick, dark liquid that clung to the glass sides of the bottle.

‘Should I mix it with his food?’ she asked.

‘With food, or with drink – but only after the food has been cooked. Or it can be given to him directly, if he will take it.’

‘Why shouldn’t he?’

‘His doctors will try to prevent you giving it to him, and in his state, he may be swayed by them. You must be determined.’

‘I will be.’

She remained kneeling, staring at the floor of the stone cell in the monastery, awaiting her dismissal. He did not delay her.

‘Go now, my child,’ he said. ‘I will pray for you both.’

The tsaritsa thanked him, then rose to her feet and left quickly. The starets stood and went to the doorless archway that formed the entrance to his cell. He watched her as she left, clearly battling against her own ill health simply to make it to this appointment, which she believed would save her husband.

She was mistaken; Iuda knew that full well as he pulled the starets’ robe off over his head. He had more work to do that night, and beneath the habit he was almost dressed for his next task. The other monks might remark on his disappearance, but they had always seen him as a nomad – a starets who occasionally used their home as a place of quiet contemplation. There were many like him.

The military were by nature far more suspicious. To have passed himself off as a soldier for any length of time would have required forged papers and – to get close to the tsar – at least one personal recommendation. But the acquisition of the lieutenant’s uniform whose tunic he was now buttoning up had been a much simpler affair – taken from a drunken soldier whose half-hearted resistance had provided little entertainment. The others might miss him, but they would not find his body for another few days, at the very least.