The light was extraordinary in this holy country, thick and dense, crushing. It seemed to oppress the old city with its broken walls and shining domes, rather than illuminate it. Thomas, utterly exhausted, felt close to collapse. But here he was before Jerusalem itself, standing in the footprints of Christ. Overwhelmed, he brushed the dirt from his robes and scraped the sweat from his brow, and dropped to his knees to pray.

He was aware of Joan and Saladin, swathed in their white Saracen-like robes, watching him with some bemusement.

Joan led him into the heart of the city, with a serving boy who spoke not a word of English or Latin following behind with Thomas’s pack. Thomas was soon lost in the maze of jumbled streets. There was a feeling of crush, of shabbiness, and Thomas saw that some of the buildings had been assembled from broken and ancient stones. Age lay heavy here.

To get to Joan’s home he was led through a narrow alley to an inner court around which tall houses clustered. Joan entertained him in a large open room, with a thick carpet and heavy hangings on the wall. The windows, just slits, were so small that oil lamps burned despite the intensity of the light outside. It was a room that might have graced an English manor, he thought. But this was not England, where you strove to keep in the warm; the room was hot and stuffy, thick with smoke, and sweat started from his brow. It was an inappropriate, stubborn architecture.

Joan served him watered wine. ‘You are an unaccustomed traveller, brother,’ she said.

‘I’m afraid so. I prefer to journey in the imagination, in the pages of my books, rather than to haul this weary carcass across land and sea.’

‘And yet you have come as far as Baldwin, and those who first took the Cross.’

‘The crusaders arrived fit to fight. They came to build kingdoms! I scarcely have the energy to make up a bed.’

‘Oh, that is done for you,’ Joan said. ‘And while we don’t expect you to conquer the city for us, you must see it. I want Saladin to show you around. No, I insist.’

Saladin nodded, looking surly, reluctant.

Joan’s English was stilted, her accent a kind he had never heard the like of before. She was a slim woman, with a pretty, oval face and a pale, very English complexion - unlike her son, who was so dark he was all but invisible in the gloom of this absurd hall. The mother looked out of place here, a northern flower that ought to wilt in the sultry fire of the sun. Yet she was prospering, even though she had lost her husband and father before she was twenty.