‘The reasons you have put forward to explain my investigation are valid, that’s certain. However, I have been wondering about your personal interest in this. General Triaire would easily have sufficed. But you and the Emperor himself! Could there be a more personal reason, Your Highness?’

‘You are wrong about the Emperor. He takes the political aspect of the problem very seriously. As far as I’m concerned, the answer is yes and no. Perhaps. In fact, probably not … There was another murder, just before the start of the campaign. I found this coincidence disturbing.’

Margont almost flew into a rage, something he did rarely. His meetings with the prince were really not good for him.

‘Another murder? And you didn’t tell me about it?’

‘No, because the culprit has been arrested.’

This new lead had scarcely come to light and it was already being snatched away. However, Margont noted that the prince did not seem convinced.

‘I should be grateful if Your Highness would tell me the story so that I can form my own opinion. Above all, do not hesitate to give me all the details. Paradoxically, the more details I have, the clearer things will become to me.’

‘Very well. This business occurred about a week before the murder of the Polish woman. Our corps was still in Poland and we were putting the finishing touches to the preparations. The Emperor wanted to be kept informed of everything. Every subject held his attention: the numbers and quality of the troops, the calibre of the officers, the supplies, the reserves of ammunition, the artillery, the clothing, respecting the privileges granted to my Royal Guard, the pay, maintaining discipline, relations with the Polish population … And His Majesty would not tolerate any delays or approximations or disappointing answers! In a word, my general staff and I were constantly in demand. So I was careful to organise regular entertainments. A mind that enjoys itself from time to time works better than one that is subject to permanent pressure.’

The prince cast another annoyed glance in the direction of poor General Triaire, who was attempting to stem the flow of missives.

‘One evening, a grand reception was given by Countess Nergiss, a Polish sympathiser. I should point out that I was not the instigator of this event. It was entirely conceived and organised by the countess. There were four hundred guests at the very least. Perhaps you were there?’

‘Unfortunately not. I am not of high enough rank to be invited.’

‘Lay your hands on our murderer and that sort of disappointment will be a thing of the past.’

‘I knew about the celebration but I didn’t hear anything about a crime …’

‘Let me continue. Countess Nergiss is as rich as Croesus and she had set her sights on an ambitious promotion for her husband, who is a general. She hoped that, if General Prince Poniatowski happened to be wounded or killed, her husband would replace him in command of V Corps, the Polish Corps. Can you believe it? So she had been preparing this reception for weeks, even before the Grande Armée reached Poland. To her chagrin, the Emperor informed her at the last minute that he would not be able to come as he was with the bulk of the army much too far north of the castle. Only IV Corps was camped nearby. The countess therefore fell back on me in her calculations, hoping that I would plead her cause with His Majesty. To make her tactic less obvious, she had decided to dazzle me. I must admit she succeeded very well. What splendour!’

The prince must, though, have been used to this type of event. Margont told himself that the countess must have beaten all records for extravagance.

‘She had invited the full complement – the full complement! – of my senior officers.’

Margont attempted to disguise his dismay. His suspects had therefore all been invited to this reception.

‘Each guest was allowed to bring up to three people. When I arrived – late because I was being informed about last-minute problems practically all the time – it was only to discover a crowd of officers, Polish nobles, notables, wives, children, soldiers on guard duty … all of them being pampered by an armada of servants. Try to imagine an immense castle. As it was a clear night, the countess had set up outside an endless array of buffets: Polish, French, Italian, Danish, Indian, Creole … Valets provided the lighting by standing still with lanterns in their hands. Any sensible person would have planted stakes in the ground to hang the lanterns on, but no! Why make savings when you can throw money out of the window? Orchestras, dotted around the grounds, were giving concerts while fireworks crackled in the sky. To mark my arrival, the entire surroundings were briefly illuminated by sparkling showers of light and thousands of fireworks. It was like being back in the extravagant era of the Sun King. But it was even better than that because this time I was the Sun King.’

Margont blinked. How could anyone be so rich? And how could they waste so much money?

‘It was so luxurious it was grotesque,’ concluded Eugène. ‘But it was ideal for taking your mind off things. I whispered to Triaire that one or two more evenings like that and though I wasn’t sure whether the count would be given command of V Corps, I’d be pleased to offer him that of IV. The countess seemed to me quite a pleasant person, in the sense that she knew how to avoid overstepping the boundaries. That’s a very rare quality among courtiers. So she vaunted her husband’s merits – he’s serving in the Polish Corps – but she interrupted herself before my irritation surfaced. She had one strange quirk: she would disappear every hour and come back showing off a new dress and different jewels, in a crescendo of extravagance. That’s exactly it! With her sapphire necklace and her champagne-coloured diamond …’

The prince had raised his voice. There was a tense sadness about him. He seemed caught in a moment of futile protest against a past that could not be altered.

‘If Countess Nergiss had not been so obsessed with luxury, everything would have turned out differently, and a young lady I thought highly of would still be alive. In short, the evening continued its pleasant course, interspersed with the extravagant follies of our hostess, including cut-crystal glasses that she cheerfully invited her guests to toss into the air as soon as they were empty, a hunting party—’

‘But it was night-time.’

‘Do you think that was a problem for the countess? She had illuminated one of her woods with lanterns and had it surrounded by beaters before getting the gamekeepers to set the deer loose. I admit that we killed far more lanterns than deer. When the wood started to catch fire because of the oil from the lamps that had been hit by the bullets, the countess declared that it did not matter. However, this silly game came to an end and the fire was brought under control at an early stage. The countess’s next stunt was to parade past me the one hundred and twenty horses of her stud farm before presenting me with one of her handsomest stallions. That evening was a folly, I tell you! On the stroke of eleven, the master of ceremonies – a man always stiff and mannered – announced that a play was to be performed. Immediately, swarms of servants busied themselves in setting up an open-air stage and laying out hundreds of chairs. When the actors appeared, I was astonished. Because I knew them.’

The prince’s voice had changed, becoming less cold and more human. His account sounded less like an official report and had become more personal. Eugène even seemed on the verge of tears. But the exercise of power had taught him to hold his emotions in check, in the same way you would train a dog. No tears flowed.

‘Yes, I knew them. It was a Parisian company I had often seen perform. Oh, they’re not very well known but … you’re bound to know … As the whole of Paris knows about it, I suppose you do too.’