"On the evening of the 22nd December," I am quoting from Mag's diaries, "in the year 1720, a drunken carpenter knocked over his oil-lamp and set fire to the shavings in his workshop. Within seconds – faster even than the blaze in the old bakehouse in Pudding Lane that had set the whole of London burning fifty years previously – almost the entire mediaeval town of Rennes went up in flames, from the Vilaine river to the old cathedral of St Peter that hovered on the edge of disintegration anyway, and would collapse soon afterwards. There was no running water in old Rennes, and consequently nothing with which to fight the blaze. People ran with buckets to and from the river – but in truth that was about as much use as what Gulliver did in Lilliput. Less use, for he was pissing on the mere scale model of a town, and downwards from a giant's height. While here the dragon went on breathing flames."

   Mag took a lodging in what was left of the old town, in the shadows of the church of St Sauveur – "dedicated to Our Lady of the Miracles who had saved Rennes from the English during the siege of 1357" – a modern apartment rather than one of the lath-and-plaster buildings that had survived the fire: only Rennes' wealthy aristocrats could afford those. There were in fact a goodly number of those mediaeval structures left, including one particularly lovely one in the Rue St-Guillaume which purported to be the former home of Du Guesclin himself – the real saviour of Rennes in the siege of 1357 - but now a cheap bistro named Ki Toz that was "as near as the French can get to a greasy spoon café", where, somewhat more prosaically, he took his supper almost daily through those first few weeks.

   But he had come to find Dahut, not the history of Brittany.

   He could have phoned of course, but that would have given her a warning that he feared might not be helpful. He could have gone round to her home – but the truth was, she had always found excuses not to give him her address. Knowing the name of the Lycée where she taught should have made it easy, but in fact she wasn't there, had never been there, was unknown to anybody in the building. The school secretary was adamant she had never heard of anyone by the name of Dahut Cudenec.

   "I've been writing letters to her at this address for the last two months. If she's not here, the letters must be."

   The school secretary searched. The admissions secretary searched. Even the secretary to the college principal was telephoned. But all to no avail. No one had ever heard of Dahut Cudenec. No one had ever seen any letters addressed to such a name.

   There were several options open to him – of which forgetting the whole damned business and going back to England was indeed one, though it flickered into his brain for no longer than the nanosecond it required to make it flicker out again. He could have phoned Robert and Madeleine; he could have phoned Marise – though he had deduced by now that this would prove a cul-de-sac. What in fact he did was to go round to the nearest post office, and verify that the address he had was the correct one.

   "Mademoiselle Cudenec?" It took them nearly half an hour. "Yes, we have instructions for a forwarding address. But we cannot give it to you."

   Mag tried to argue, but there was little point. Like officials everywhere, they were only obeying orders. Instead, he went to the nearest café and wrote a long letter to Dahut, mailing it to her school address, letting her know that he was now in Rennes, that he had failed to find her at the school, that he understood the post office would forward this to her. He gave her his address, and told her he would eat supper at 6.30 every evening at Ti Koz, Du Guesclin's restaurant on the Rue St-Guillaume. Knowing how much she hero-worshipped Du Guesclin, and knowing even more her love of symbols, he was confident she would eventually respond. The invitation to join him on any one of these occasions was an open one. He trusted she would find an occasion to accept, and required no forewarning. Then he closed with the words "Best Wishes", deliberately crossed them out, wrote "With All My Love", and signed it, using the wax from the red candle on the table to make a sort of regal-looking seal on what was a deliberately formal letter. He hoped it would seem regal in the strict sense. The signature within the seal: Roi Gradlon-Meur.

   She never came.