Geoffrey led Harry, not to the door of the church as he had expected, but to a side wall. Here a kind of cell protruded from the church’s wall, with no door, and no window save for a slit.

And here, Geoffrey said, was his sister: bricked up in the cell within which she would spend her whole life. Harry stared in horror.

Geoffrey touched his shoulder. ‘You must try to understand. This is the life your sister has chosen for herself. And she serves her people, you know. As the father said, most parishes are proud to have an anchoress attached to their church.’

A voice floated up from the slit window. ‘Geoffrey Cotesford? Is that you?’

The tone was deeper than it had been, softer, but it was unmistakable. Harry’s heart thumped; he had not realised how much he had missed his little sister.

‘It is Geoffrey.’

‘I knew you’d return.’

‘Your faith in your brother was justified too.’

She gasped. ‘Harry?’

Harry forced himself to speak. ‘I’m here, Agnes.’

‘Then come to my window.’

Harry knelt down. The window was a slit, just large enough to pass food and waste. Only a little light leaked into the cell within. He could see another window on the far wall where the anchoress was able to look into the church. The room was simply laid out, with a bed, a bench, a table, a crucifix on the wall. On the table were two books, a leather-bound Bible, and a copy of the Ancrene Wisse, the manual of the anchoress. The room’s only other feature was a shallow trench in the floor. It puzzled Harry, who knew little of the lifestyle of an anchoress, a walled-in hermit.

And through the squint, this slit window, his sister’s familiar blue eyes gazed out at him. ‘I prayed you would come. I knew you would. You always did protect me, Harry.’

But, he thought, I did not protect you from this morbid fate. ‘I have news of the family,’ he said.

‘My father is dead,’ Agnes said softly. ‘I know that much.’

‘Mother is well. She misses you.’

‘Tell her I pray for her . . .’

Geoffrey interjected gently, ‘I will leave you to talk. But we must turn to business. Harry needs to understand why you summoned him, Agnes.’

‘I would not have disturbed you,’ she said. ‘But I had to.’

‘Why?’

‘Because of what I found. In this cell . . .’

And she spoke of family legends: of Orm, who may or may not have sailed with the Conqueror, and Eadgyth, or Edith, the wife he may or may not have found demented and raving in the ruins of an old Saxon church outside York, while William’s Norman thugs rampaged across the north of England.