'Above all, remember to disguise your voice if anyone should speak to you. They did not hear mine. And pretend to be dreadfully upset. That will make a good impression. Oh—' Suddenly, she had remembered the precious trust she carried in the little wash leather bag close to her breast. 'Would you like me to give you back the diamond?'

'No. Keep it. And do exactly as I told you. It belongs to the one of whom I spoke. In four months' time, a man will come to the rue de Lille and ask you for it. You have not forgotten?'

She shook her head, then pushed him gently towards the door, on the far side of which the heavy, nailed boots of the guard could already be heard climbing the stairs.

'Take care!' she whispered again, then ran to throw herself down on the heap of straw which had been strewn for a bed in the darkest corner of the cell. She burrowed down in it as far as she could, hiding her head in it and in her folded arms, like someone in the depths of despair. There, with her heart thudding anxiously, she waited.

There was the clang of bolts being shot back. The door creaked. Then came the rough voice of the grenadier.

'Sorry, m'lady – time's up.'

He was answered by a high-pitched sob which did credit to the cardinal's dramatic talents. Then the door shut again and the footsteps died away. Even then, Marianne dared not move. Her whole being was strained, listening while she counted the interminable seconds in time to the laboured beating of her heart. At every moment she expected to hear an angry shout, sounds of a struggle, of voices calling for the guard. In her mind's eye, she followed the progress of the prisoner and his guide. Down the stairs to the first landing, the second flight and then the guardroom – and the door itself.

She breathed more easily when she heard the heavy boom as it swung to, echoing up from below. Gauthier de Chazay was outside now, but he still had to reach one of the three gates of the Kremlin unrecognized. Fortunately, to judge by the increasing gloom inside the prison, it must be even darker than before outside. It was as well the cell itself was spacious and high-ceilinged or there would have been a real risk of death by suffocation.

Marianne got up at last and paced a few steps up and down her prison. A puff of acrid smoke caught her throat and made her cough. At that she tore a piece out of her petticoat and, dipping it in the traditional pitcher of water which stood in a corner of the cell, applied it to her burning face. Her heart had been beating so wildly that she felt quite feverish but she forced herself to think calmly.

It would not be long before they came for the prisoner. What would happen then? They would scarcely do her any actual injury, being a woman, but she would be taken before the Emperor without delay and, for all her courage, she could not help shivering a little at the thought of what lay before her. It was certainly not going to be pleasant. But a man's life, Gauthier de Chazay's above all, was surely worth a little unpleasantness, even if it were to end in prison. It was as well that Jolival had made few difficulties when she disclosed her intention to him. He had even agreed to do as she asked him.

"You had better be out of the way of the Emperor's wrath,' she had told him. 'Gracchus can arrange to get you out of the Kremlin. You might go back to the Rostopchin Palace – unless the fire spreads so much that you are obliged to quit Moscow. In that case, let us agree to foregather at the first posting house on the road to Paris.'

With her mind at rest on that score she had paid scant attention to Gracchus's disapproving sniffs, merely remarking that if people could not obey her orders, they had no business in her service. Then, with the matter of her companions satisfactorily dealt with, she had been free to concentrate on the plan of escape which now seemed in a fair way to success.

The hardest part was going to be the waiting, how to get through the time that must elapse before the escape was discovered. She calculated that the time must be about midday so that, unless the Emperor should decide to evacuate the Kremlin, it might be six or seven hours before anyone entered the cell. Six or seven hours! Six or seven times eternity!

A lump settled in Marianne's throat and she felt herself a prey to the panic of a small girl locked in a dark cupboard. She wanted desperately to get it over and yet she knew that the longer she was left to endure her torment, the greater the cardinal's chances of escape. She must be patient and, if she could, keep calm.

Remembering suddenly that she had eaten nothing since the previous night, she went to the niche in the wall where stood the pitcher of water and a crust of bread. But it was her will more than her appetite that forced down a little of the dark, rock-hard bread. She knew that she must keep up her strength, yet she was not conscious of the slightest hunger. On the other hand, the smoke that was creeping into the room rasped her throat and she swallowed half the contents of the pitcher at a draught.

The heat was becoming uncomfortable and when she approached the narrow slit which did duty as a window she was horrified to see nothing but a mass of flame. The whole southern part of the city must have been on fire. The Kremlin itself might be entirely surrounded. The fire was reflected in the river so that even that seemed to be on fire.

Still nibbling her piece of bread, she had begun walking slowly back and forth across her prison, partly as a cure for impatience and partly to calm her nerves. But all at once she stopped dead, listening with all her might, while her heart beat a little faster. They were coming. There were men coming up the stairs, making all the characteristic noises of soldiers carrying weapons. Marianne's mind leapt to the conclusion that the hour of the trial had been put forward and they were coming for the prisoner. The Emperor must have decided to abandon the Kremlin.

She tried feverishly to reconstruct the route the prisoner would have to follow. He must have succeeded in negotiating the fortified perimeter. But she had been so anxious that her estimate of time could have gone very much awry. Had he really had time to reach safety?

There was a grating of bolts and Marianne stiffened, clasping her hands tightly together until the bones cracked in the way she had when striving to control her feelings. She heard people enter. Then a voice spoke, a very youthful voice but stern and carrying.

'The court awaits you, Sir. If you will come with me—'

In such time for thought as her brief imprisonment had allowed her, Marianne had not managed to decide on the right course to pursue when her substitution should be discovered. She was relying wholly upon instinct but, determined to gain as much time as she could, she had withdrawn, at the sound of approaching footsteps, to the darkest corner of her cell, keeping her back to the door.

Not until she was spoken to did she turn to see, framed in the doorway, a young captain, a stranger to her, and two grenadiers. The captain was slim and fair, straight as a ramrod and rather touching in his dignity. It was clear that he was immensely proud of the mission entrusted to him. It was his moment of glory and he was going to be cruelly disappointed.

Marianne advanced a few steps into the light that entered from the staircase. Three separate gasps of astonishment greeted her appearance. But by that time Marianne had made her decision. Gathering up her skirts, she darted through the gap between the two soldiers and plunged down the stairs, descending them like lightning before the men could recover from their surprise. She had reached the guardroom before she heard the young captain shouting: 'What the devil! Well, after her, damn you! Don't stand there gawping! Catch her!'

It was too late. Luckily for Marianne, the tower door had been left open. She was outside before the guards had even started after her. With a triumphant gasp, she plunged into the smoke as though into a protecting fog and ran straight ahead, regardless of possible obstructions, spurred on by the one thought of all escaping prisoners: to put as much ground between herself and her pursuers as possible. But the way sloped steeply uphill to the terrace and behind her she could hear shouts and yells that sounded horribly near.

She did not know the Kremlin or its exits and those portions of the upper terrace that she could see through the smoke looked hopelessly full of people. She had to find some way or other of concealing her identity if she did not want to be caught between two fires.

She was still wondering where to go when she caught sight of a tree not far from the top of the grassy slope, close up against one corner of the palace. It was an old tree, several hundred years old certainly, and its branches dropped wearily down to the ground. It was twisted with age but the mass of its foliage looked impenetrable. The noise of the wind in the leaves was like a rookery in full voice.

Running before the wind, which was now gusting strongly from the south, Marianne found herself at the top of the slope, right up against the trunk. She measured the distance with her eye and decided that in the ordinary way it should not prove too difficult to climb. But would her injured shoulder allow her to do what would have been easy for her before?

It is a well-known fact that the love of liberty can lend wings to the least able and, all things considered, Marianne had no wish to confront the anger of Napoleon. What she wanted more than anything in the world at that moment was to find her friends and be gone from that accursed city as soon as possible. Gasping with pain, but spurred on by the desperate longing to escape, she managed it. After what seemed an age but could not have been more than a few seconds, she found herself seated astride one of the great branches and completely hidden from below. She was only just in time. A bare half-minute later she saw her young captain pass directly beneath her. He was running like a hare and shouting 'Guards! Guards!' at the top of his voice, regardless of the blazing debris falling all about him.