The window opened with a squeal of swollen wood and she clambered in over the sill. But the sill was so wide, because of the thickness of the wall, that she ended up falling into the passage.

As she scrambled to her feet, a figure stepped into the passage from one of the rooms ahead: a tall, thin man dressed in corduroy trousers and a bulky sweater. He had lank grey hair and a narrow, bony face. His sunken eyes peered at her from behind black-framed glasses.

Wada took all that in at once, but somehow failed to notice the double-barrelled shotgun he was holding in his hands until he raised it to chest height and pointed it straight at her.

‘Who are you?’ The voice was gruff, as if from lack of use. The accent was that of a well-educated Englishman.

She stared at him, unable for the moment even to speak.

‘Who are you?’ he repeated.

She had to say something. But the truth might be as fatal as a lie. Who was he became the vital question.

And the answer came to her as she looked into his raw-rimmed blue-grey eyes. He was Martin Caldwell. In the end, there was no one else he could be. ‘I am the woman you were supposed to meet in London,’ she said quietly.

‘No you’re not. She never left Tokyo.’

‘If you mean Mimori Takenaga, then, yes, you are correct. My boss sent me to see you posing as her because her family would not let her leave the country. My name is Wada.’

‘And your boss’s name?’

‘Kodaka.’

‘Who met with a fatal accident last week.’

‘That is also correct.’

‘Why didn’t you give up then, with Kodaka dead and his client, as I understand it, confined to a psychiatric hospital?’

‘Why did you not meet me as planned in the British Museum?’

‘I got held up here.’

‘Will you lower the gun, Mr Caldwell? You are making me nervous.’

‘You don’t look nervous.’

‘But I am.’

‘How did you know I was here?’

‘I did not know you were here.’

‘Then why did you come?’

‘Please lower the gun, Mr Caldwell.’

‘First tell me what brought you here.’

‘The Emergence files in Quartizon’s offices. Kristjan and I found out what was in them.’

‘And what is?’

‘Grid references for parcels of land all over Iceland, apparently owned by Quartizon. Including this parcel of land. But Stóri-Asgarbær seems to be different from the others. It’s not part of whatever’s planned for Wednesday.’

‘Where’s Kristjan now?’

‘Under arrest.’

‘How did you get away?’

‘I was lucky.’

‘Well, maybe your good luck is my bad luck.’

‘I am not a threat to you, Mr Caldwell. I am not your enemy. Please lower the gun.’

Something softened in his expression. He turned the gun away. ‘I’d never have fired, Miss Wada. I’m not a killer.’

‘I never thought you were.’