‘That’s how I thought it would be – I would look after Hattie and care for her. I never dreamed –’

‘You never dreamed – and your son carefully did not tell you, that at the time of the marriage he was already married. Oh, yes – we have searched the records for what we knew must exist. Your son had married a girl in Trieste, a girl of the underground criminal world with whom he concealed himself after his desertion. She had no mind to be parted from him, nor for that matter had he any intention of being parted from her. He accepted the marriage with Hattie as a means to wealth, but in his own mind he knew from the beginning what he intended to do.’

‘No, no, I do not believe that! I cannot believe it…It was that woman – that wicked creature.’

Poirot went on inexorably:

‘He meant murder. Hattie had no relations, few friends. Immediately on their return to England, he brought her here. The servants hardly saw her that first evening, and the woman they saw the next morning was not Hattie, but his Italian wife made up as Hattie and behaving roughly much as Hattie behaved. And there again it might have ended. The false Hattie would have lived out her life as the real Hattie though doubtless her mental powers would have unexpectedly improved owing to what would vaguely be called “new treatment.” The secretary, Miss Brewis, already realized that there was very little wrong with Lady Stubbs’ mental processes.

‘But then a totally unforeseen thing happened. A cousin of Hattie’s wrote that he was coming to England on a yachting trip, and although that cousin had not seen her for many years, he would not be likely to be deceived by an impostor.

‘It is odd,’ said Poirot, breaking off his narrative, ‘that though the thought did cross my mind that De Sousa might not be De Sousa, it never occurred to me that the truth lay the other way round – that is to say, that Hattie was not Hattie.’

He went on: