‘We don’t know. Is Ann allowing her imagination to run riot? Is she fabricating Mary Elizabeth Rolfe? No. For when she first did this in Bristol and Dr Bourne saw how consistent the Mary Rolfe personality was, he tried to check-up to see if such a person ever existed or if a Mr Rutherford had lived at Thirty-eight Belgrave Square, London. When he found that there had indeed been a family of that name living at that address in eighteen-eighty-six he became very interested. So he tried to check on Arthur Howard, mentioned by “Mary” as living at Ardvreck House in eighteen-eighty-eight.’

‘I was rather taken aback when that checked out as well,’ said Bourne. ‘And rather disappointed.’

‘Disappointed?’ Neither Carol nor Paul could see why this second confirmation had had that effect.

Meredith smiled.

‘Arthur Howard was relatively famous in the annals of crime. He had been acquitted on a charge of murdering his wife, been sought by the police in connection with insurance swindles and certain sudden if convenient deaths. And had disappeared without trace thus successfully evading the course of justice.’

‘But I still don’t see – ’

‘Ann may at some time in her life have read of the case of Arthur Howard and forgotten consciously that she had done so. In the hypnotic state, with her greatly enhanced powers of recollection, she could be recapturing that data, dramatizing it and acting out the role of Mary Rolfe. Such presentation of information, once memorized but subsequently forgotten, is not unknown. There’s even a name for it – cryptomnesia.’

Pollard frowned.

‘Do you believe that in this case?’

‘Well, not really. There’s too much additional evidence. But one must keep an open mind. Anyway, at this point, Dr Bourne got in touch with me and I was able to give him another surprise, namely, that Ardvreck House also occupies a famous place in the annals of psychical research.’

‘The Bernard Gray case?’

Meredith’s face was sombre in expression.

‘Yes, the Bernard Gray case.’ He looked at the hypnotized young woman. ‘So we decided that we would try to devise some means of testing the cryptomnesia theory. If that could be disposed of, then we would be free to consider the other possibilities more closely.’

For the first time Sergeant Smith spoke.

‘Other possibilities?’

‘Yes, Sergeant. For example, that Ann Parish in a previous life was Mary Elizabeth Rolfe.’

‘But . . . You mean reincarnation?’ The disbelief in Smith’s voice was patent. ‘You don’t go for that old superstitious rubbish. When you’re dead, you’re dead.’