When my client departed he did not look very hopeful of the results of my investigations, and although my plans were already laid, I was not at all sanguine as to their success.

But of two fundamental facts I felt certain. Mrs Wemysson had committed some indiscretion, in which the welfare of her step-daughter was involved. And Mr Jackson was not only cognisant of that indiscretion, but was determined to make capital out of it.

Now, whatever the indiscretion was, it had evidently had its origin at Monte Carlo. It was probably connected with Mrs Wemysson’s rashness at the gaming tables. But at this point the puzzle became more tangled. Even if she had been losing money heavily, this would not make marriage into her family desirable for an impoverished fortune-hunter, for that Mr Jackson had actually fallen in love with Alice Wemysson was, I concluded, hardly a likely supposition to entertain. I preferred to look upon his motives as entirely mercenary.

Suppose Miss Wemysson proved to be a greater matrimonial prize than she knew herself to be? This would explain the solicitor’s conduct in forcing his attentions upon an unwilling girl. But it made the widow’s behaviour all the more inexplicable.

With a view of satisfying myself as to Miss Wemysson’s financial position, I communicated with one of the employees of the bank in which her father had invested his money, and desired him to let me know how much of this money had been withdrawn. We make a point of having friends in all sorts of unlikely places, and their co-operation often simplifies our work wonderfully. In this case the information I got startled me considerably.

Of the twenty thousand pounds left by Mr Wemysson, there was barely five thousand left! Mrs Wemysson must have been completely carried away by the gambling demon, to risk her daughter’s little fortune as well as her own. Mr Jackson evidently knew of her breach of trust and was trading upon it. Now where did his profit come in?

I determined to know.

A few days later, having watched him leave his office, I interviewed the poor underpaid soul who served him as clerk. At first I could get little information from him. But, prompted by the promise of another situation, he showed me what a scoundrel his employer really was.

Mr Jackson knew that Mrs Wemysson had gambled her daughter’s money, and threatened to expose and ruin her if she did not insist upon Alice marrying him. He forebore to tell her that Mr Wemysson’s brother, of whom they had not heard for years, had died and left his niece a fortune of fifty thousand pounds. He, as the family solicitor, knew all about it, but was keeping the information back until he had secured the heiress for his wife.

My course was now plain. I paid a visit to Mrs Wemysson and proved to her that I knew more about her own and her daughter’s affairs than she did. She was very humble and repentant. She was also grateful when I undertook to smooth over the ruffled feelings of the injured lovers.