But she was still young and new and fresh, as the saying goes, and had ambitions above mere survival. Life burned in her and would not be easily quenched. The clarity of her vision was remarkable: she had a sophistication of thought far beyond her sex, or station or age. Listen:

'Do not think I do not understand what I am doing. I could become a flower girl, or a shop worker or labour in a factory. I might find some drunken soldier who would beat me and leave me. Or be forced to live with a man far more stupid than I am and defer to his obtuseness in exchange for security. What I do now may not prevail. I might sink to the bottom, and live out my days wheedling ever more disgusting men for a few sous. "Hello, dearie, want a good time?" I've seen it all. It is one future that may become mine.

'But only one, and it is not inevitable, whatever the moralists tend to think and hope. I might do better. I am prepared to gamble, and if it does not work, then I will at least end my days in the gutter knowing that I have tried.'

Lefevre made her a proposition. In exchange for any information she might provide, he would offer payment. Gold for betrayal; the most essential of human transactions, but he attempted to disguise it by subtle words and careful phrasing. She saw through them all immediately.

'What sort of information do you have in mind? We are in a border town full of troops. I imagine that is the sort of information you require.'

'Café gossip, tales of troop movements, training. Who is up and who is down in the army.'

She pursed her lips. Very well-formed lips, wide and curving, touched up by only the faintest art. 'That is all very well, I imagine, but hardly vital. What country do you come from? Or work for? I will not spy for the Germans.'

'We do not work for the Germans,' he replied.

'Probably the English, then. Or the Russians.' She considered. 'I think I could manage that. Depending on the price, of course. But I think you set your sights too low.'

'How is that?'

'The whole of the general staff is here. Would it not be better to have information from that quarter, rather than café chit-chat?'

Lefevre did not reply.

'You have made me a proposition, Monsieur. I will make you one. I do not want to spend my life in the company of soldiers. But to present myself to better society I need clothes, jewels, somewhere better to live.'

She stopped, for what she had in mind was clear enough.

'And how much would you suggest?' Lefevre said dryly.

'About a thousand francs.'

He laughed, then shook his head. 'I think not, my girl. I do not have such sums at my disposal and if I gave it to you I doubt I would ever see it again. You'd be on the next train out with a different name. Do you take me for an idiot?'

I abbreviate, and my memory does not recall the exact words, but that was the essence of the conversation. It was illuminating; I considered that Lefevre had made a mistake, and that I had seen one of his limitations. He did not think broadly and was cautious in his judgement. Perhaps he was right; experience had taught him that neither men nor women were to be trusted. But I believed I had seen something he either had not glimpsed or wished to disregard.

The girl was clever. I do not mean sly, or cunning, although life had taught her much of that when it was needed. But intelligent. She saw a chance for herself. She did not, I noted, threaten – did not say she would go to the authorities and report us, which was just as well for her. She judged the situation clearly.

And even in her situation – which was poor and could easily have been squalid – she somehow rose above circumstance. She dressed well considering the quality of her clothes; she sat and talked properly. There was an animation in her eyes and expression which made one forget that she was neither particularly beautiful nor favoured in life. Even Lefevre did not address her too roughly or rudely. She had character, in sum, and I believed it was a pity to waste it.

You note I talk here entirely without reference to morality. Let me rephrase it; we were talking to a whore about how to be better at her trade and I was considering seriously that we should act in some way as her pimps. Express it in such a way and it is shocking; I was already a long way from home. Yet I did not see how her life could be made worse, or her soul even more imperilled, by the course she wished to pursue. And there might be gain all round. I put my argument to Lefevre afterwards.

He dismissed it. 'A thousand francs? For a girl who charges two francs a night? Are you serious?'

'How long are we staying here?'

'Until we're finished.'

I scowled. 'Tell me.'

'Why?'

'Because I would like to talk to that girl again.'

He shook his head. 'No. I forbid it.'

I found her again the following evening, walking across the Place Stanislas. Even from a distance I could see the effect she had: men walking towards her would slow down as they passed; some nodded, uncertain whether she was signalling to them. Poor as she was, she was so far above the normal that there was doubt. She was not brazen or vulgar; she attracted through an appearance of vulnerability and delicacy. I briefly considered the fate that lay before her, how that delicacy would be trampled and ruined, and shuddered slightly. I had seen in her eyes the day before that she knew exactly how her future could develop.

A man began talking to her as I approached; I bristled somewhat at the indignity, and so hailed her in a louder voice than I might otherwise have used.

'Good evening, Madame, I am so sorry to have kept you waiting.'

The effect was delightful; he froze with horror at the evident mistake he had just made, gave me one brief look and ran as fast as he could. Virginie looked at me coldly.

'You will have to pay for that,' she said.

'I intend to. Have you eaten this evening?' It was nearly eight o'clock by then and already dark and cold.

She hadn't, so I took her to a restaurant. A moderately expensive one, deliberately chosen, as I wished to see how she would conduct herself, how much she knew about manners.

Although by far the worst-dressed woman in the place, she did not allow herself to be abashed by her obvious poverty. She behaved to the waiters with proper grace, did not allow her voice to rise as the alcohol seeped into her blood, chose her food cautiously but well, ate with delicacy. And the waiters responded; she did not flirt with them, but she made herself attractive in a distant, untouchable fashion. She got better service than I did; by the end of the meal she was getting more attention from them than anyone else in the dining room.

We were halfway through the first course when I realised I had quite forgotten who and what she was, and brusquely brought myself back to earth. 'I must ask you for some information,' I said. 'I'm afraid I do not understand you at all, and that could be a grave impediment to any business arrangements between us.'

She looked at me evenly, not perplexed, as she was already far beyond that stage. At no point so far had she asked me any questions at all, which was a good sign.

'I have been thinking about what you said yesterday,' I continued. 'My associate,' we had not given her any names, 'is not interested in your proposal, but I see some possibilities.'

Much later she told me how excited she had been by this remark; so overwhelmed that she did not know how she had prevented herself from bursting into tears. All I can say to that is that her self-control was remarkable; not a flicker of any emotion passed over her face. Had I known how well disciplined she was, I would have engaged her on the spot.

'But I need some answers from you.'

'What exactly?'

'I need to know whether you will be capable of filling the role you desire for yourself. A gentle nature, and pretty face will not be sufficient. You need also to be . . .'