‘Well, really, Meredith, I must protest at this utterly unjustified and totally irresponsible speculation. It is not going to help our experiments if we are all going to be looking fearfully over our shoulders for bogeymen.’ He looked scathingly round the room. ‘I may say that I intend to get as good a night’s sleep as is possible in that rather less than five-star bedroom you’ve put me in.’

Listening to Bourne’s acid tones, Paul realized he had arrived at a moment of decision. The bickering discussion, following as it did the long-drawn-out search and painstaking sealing of the house, had finally undermined the suspicion that these people were united in some elaborate hoax to bemuse Carol and himself. He found himself accepting them at face value, three groups, scientists, army men and TV team, met in this age-crazed old house for various reasons.

‘Before we go any further,’ he said, ‘I think there is something else I should tell you.’

‘Something else?’ Meredith, about to reply to Bourne, shot a questioning glance at Paul.

‘Yes. Something that happened last night.’

He had their attention. Slowly at first, reluctantly, he began to recount his experiences of the disturbing noises from the seven-sided room above his bedroom, of how he had gone upstairs to investigate.

‘Well,’ Hunt breathed. ‘I do hand it to you, Wilson. I certainly wouldn’t have gone up that stair alone. Weren’t you scared?’

‘Scared spitless.’ Hunt grinned at Paul’s use of his own phrase.

Bourne rested his chin in his hand.

‘You say these noises were loud?’

‘Yes.’

‘Yet your wife did not wake?’

‘No.’

‘Is she normally such a sound sleeper?’

Paul hesitated, cursing himself for doing so. Meredith stirred.

‘Remember, Bourne, they’d had a long and tiring journey.’

‘Why didn’t you wake her?’ Bourne pursued.

‘Because I felt – well, I saw no reason to. It might have alarmed her.’

‘So we have only your word for the whole thing.’

‘Y-yes.’

‘Like the man you saw at the window.’

Paul felt his face flushing at the tone in Bourne’s voice.

‘Why didn’t you tell us this morning?’ Bourne asked. ‘You do remember that I asked you if you’d slept well?’

‘I do remember.’ He found himself gazing almost defiantly round the group. ‘But I believed we would be leaving shortly. And – ’

‘And?’ It was Pollard who repeated the word.

‘Well – ’ He stopped, took a deep breath. ‘I simply did not know what was going on. I felt it best . . .’ He shrugged. Pollard nodded.

‘Felt it best to keep a low profile. Yes. I think it’s understandable, Dr Bourne, that he should keep quiet this morning.’

Bourne said nothing. The sceptical look on his face remained.

‘Well,’ said Pollard. ‘I don’t know what to suggest. What do you think, Dr Meredith? What’s the chance of these noises being heard again tonight? Should we set up some kind of watch system?’