‘One in three,’ said Robertson. ‘Why should we be surprised when it affects us, or our loved ones? Yet still we ask the question.’

‘What question is that, sir?’

‘“By thy long grey beard and glittering eye, Now wherefore stopp’st thou me?”’ Robertson smiled sadly. ‘We never expect it to be us, do we?’

Cooper didn’t know what to say. He was starting to feel very uncomfortable, and slightly queasy. He wasn’t sure if it was the tea or all the talk of decomposition.

‘Thank you for your help, Professor,’ he said. ‘I have to go now.’

‘A shame. You never did explain your interest in the sarcophagus. Does it relate to your enquiry into the human remains found at Litton Foot?’

‘No, it was something in one of the messages.’

Robertson had his back to him at that moment, pouring himself another drink. But Cooper saw his shoulders stiffen, his head come up with sudden interest. For a second, their eyes met in the mirror over the TV set. Cooper felt himself being probed again, as if the professor had found more depths in him than he’d anticipated.

‘Messages?’ he said.

Robertson turned, raising the glass of whisky to his face, but not drinking – an old trick to hide the expression, or to distract attention from the eyes.

‘I probably shouldn’t have mentioned them,’ said Cooper.

‘That sounds intriguing. Do tell.’

‘I’m sorry, sir, I can’t. It’s not really relevant to my present enquiry.’

‘Oh, a different enquiry altogether? Something I can help you with, though?’

‘I don’t think so, Professor. Thank you.’

For the first time, Robertson had lost his affability. He couldn’t hold the glass to his lips any longer without taking a drink, or it would have looked odd. He gulped a half-inch of whisky, and put the glass down. Cooper caught an irritable gleam in his eyes, a downwards curve of his mouth, as if the malt had turned sour in its bottle.

‘Well, I really must be going,’ said Cooper.

Robertson was still thoughtful as he accompanied him to the door and on to the gravel drive.

‘Tell me, those questions about Alder Hall – were those related to your messages? And decomposition. Why did you ask me about decomposition?’

‘Professor, I’m sorry –’

‘You haven’t been entirely honest with me, have you?’

‘I wish I could share everything with you, Professor, but I’m working under certain limitations.’

‘Limitations, yes,’ said Robertson. ‘We all work under limitations, don’t we?’

Chapter Twenty-Five

Chapter Twenty-Five