‘So you don’t want to bother the police,’ Paul summarised. ‘OK. There must be some other way of finding out whether he’s been here.’

‘Well, I can’t think of any.’

‘You said he was coming here to do some research.’

‘Yes.’

‘And where would he go to do that?’

I shrugged, a little helplessly. ‘I don’t know, really. The library, perhaps, or the château … no, wait,’ I broke off suddenly, remembering. ‘He did say he was meeting someone. Some man who’d read one of Harry’s articles and was offering some useful information about tunnels.’

‘You’re sure it was a man?’

I thought back, closing my eyes as I replayed the week-old conversation in my head. ‘Yes, positive.’

‘Remember his name?’

‘No.’ I opened my eyes again, faintly frustrated. ‘No, I don’t. I think he only said the first name.’

‘Is he French or English?’

‘French,’ I said with certainty. ‘He wrote his letter in French, I do remember that, only Harry said the fellow must know English because the article – the article about Queen Isabelle’s treasure – had been published in an English journal.’

‘Right,’ said Paul. ‘So we’re looking for a local history nut who knows the tunnels pretty well and reads British history journals.’ He smiled at me above the burning cigarette. ‘Sounds like a case for Sherlock Holmes.’

‘Impossible, you mean.’

He grinned. ‘I mean it’s something I could probably look into for you. I don’t think there’d be too many guys in Chinon fitting that description, and the few who do must hang around the library. It’s just down the street, here,’ he nodded out the window. ‘I can drop in tomorrow, if you like, and ask around. And if you want to take another look around the chapelle to see if your cousin left anything else there, I’m sure I could sweet-talk Christian into lending me the keys.’

‘Would you?’

‘Sure. Sweet-talking is one of my specialities.’ He smiled, blowing smoke. ‘I have to do a lot of it with my brother.’

I smiled back. ‘Where is Simon, by the way?’

‘Don’t know. He took off after lunch, treasure-hunting, and I haven’t seen him since. After last night’s ghost story, he’s been unstoppable, you know – two Isabelles, two hidden treasures, twice the chance of finding something.’

‘Look on the bright side,’ I told him. ‘At least he won’t be quite so eager to leave Chinon, now. You’ll get to stay a few more days.’

‘Longer than that,’ he reminded me, sagely. ‘Don’t you remember? The Echo told Simon he’d never get me to leave.’ Leaning back, he stretched his arms above his head.‘Listen, do you want a drink or something? Coffee?’

I looked round the deserted room. ‘Is the bar open, then?’

‘Oh, sure. Thierry’s in the back room, doing paperwork.’

‘Paperwork?’ It seemed an odd thing for the bartender to be doing, and Paul smiled at my reaction.

‘Yeah. I think the receptionist, Gabrielle, is helping him.’

‘Oh, I see.’ I smiled back, as comprehension dawned.

‘I’m supposed to whistle if I want anything.’

He had to whistle twice, in fact, before we heard a stirring from the room behind the bar, and a slightly muffled voice said: ‘Ho-kay, just a moment.’

Across from me, Paul struck a match to light another cigarette, his eyes faintly apologetic. ‘Chain-smoking, I know. My mother would have a fit. But I have to enjoy it while I can, before Simon gets back.’

I bit my lip, thinking. ‘Paul …’

‘Yes?’

‘You won’t tell anybody, will you, about my cousin’s coin?’ If he’d asked ‘why not?’ I would have had a devil of a time explaining. One couldn’t very well explain a feeling. And that was all it was – a feeling, an irrational suspicion that things were not quite what they seemed to be among my fellow guests. I’d felt it that first night at dinner, and again last night, here in the bar – that sense of something darker running underneath the surface, some troubled current that I couldn’t understand. It reminded me of the time, years ago now, when my father had taken us to London to see a play, only he’d read the tickets wrong and we arrived just as the second interval was ending. I’d sat through the final act in absolute confusion, with the motivating plot-lines of the characters long since laid out and set in motion, so that while I felt their conflict and the atmosphere of tension, I had no idea what was going on.

But whatever the cause of the atmosphere of tension here at the Hotel de France, it didn’t seem to have touched Paul Lazarus. ‘Of course I won’t tell anyone,’ he said. ‘Not if you don’t want me to.’

‘Not even Simon?’

‘Not even Simon.’

‘Thanks,’ I told him. ‘You’re an angel.’

Smiling, he balanced his cigarette on the edge of the ashtray and leaned back in his seat, arms folded complacently across his chest. ‘I do my best.’

‘Aha!’ Simon, coming round the bar door, skewered Paul with a smugly triumphant look. ‘I knew I’d catch you at it sooner or later, I just knew it!’