Monica, John,' she cried, 'and half a sovereign if you reach it in twenty minutes.'

"This was quite too good to lose, Watson. I was just balancing whether I should run for it, or whether I should perch behind her landau, when a cab came through the street. The driver looked twice at such a shabby fare; but I jumped in before he could object. 'The Church of St. Monica,' said I, 'and half a sovereign if you reach it in twenty minutes.' It was twenty-five minutes to twelve, and of course it was clear enough what was in the wind.

"My cabby drove fast. I don't think I ever drove faster, but the others were there before us. The cab and the landau with their steaming horses were in front of the door when I arrived. I paid the man, and hurried into the church. There was not a soul there save the two whom I had followed and a surpliced clergyman, who seemed to be expostulating with them. They were all three standing in a knot in front of the altar. I lounged up the side aisle like any other idler who has dropped into a church. Suddenly, to my surprise, the three at the altar faced round to me, and Godfrey Norton came running as hard as he could towards me."

"Thank God!" he cried. "You'll do. Come! Come!"

"What then?" I asked.

"Come man, come, only three minutes, or it won't be legal."

I was half dragged up to the altar, and before I knew where I was, I found myself mumbling responses which were whispered in my ear, and vouching for things of which I knew nothing, and generally assisting in the secure tying up of Irene Adler, spinster, to Godfrey Norton, bachelor. It was all done in an instant, and there was the gentleman thanking me on the one side and the lady on the other, while the clergyman beamed on me in front. It was the most preposterous position in which I ever found myself in my life, and it was the thought of it that started me laughing just now. It seems that there had been some informality about their licence, that the clergyman absolutely refused to marry them without a witness of some sort, and that my lucky appearance saved the bridegroom from having to sally out into the streets in search of a best man. The bride gave me a sovereign, and I mean to wear it on my watch chain in memory of the occasion."

"This is a very unexpected turn of affairs," said I; "and what then?"

"Well, I found my plans very seriously menaced. It looked as if the pair might take an immediate departure, and so necessitate very prompt and energetic measures on my part. At the church door, however, they separated, he driving back to the Temple, and she to her own house. 'I shall drive out in the Park at five as usual,' she said as she left him. I heard no more. They drove away in different directions, and I went off to make my own arrangements."

"Which are?"

"Some cold beef and a glass of beer," he answered, ringing the bell. "I have been too busy to think of food, and I am likely to be busier still this evening. By the way, Doctor, I shall want your co-operation."

"I shall be delighted."

"You don't mind breaking the law?"

"Not in the least."

"Nor running a chance of arrest?"

"Not in a good cause."

"Oh, the cause is excellent!"

"Then I am your man."

"I was sure that I might rely on you."

"But what is it you wish?"

"When Mrs. Turner has brought in the tray I will make it clear to you. Now," he said, as he turned hungrily on the simple fare that our landlady had provided, "I must discuss it while I eat, for I have not much time. It is nearly five now. In two hours we must be on the scene of action. Miss Irene, or Madame, rather, returns from her drive at seven. We must be at Briony Lodge to meet her."

"And what then?"

"You must leave that to me. I have already arranged what is to occur. There is only one point on which I must insist. You must not interfere, come what may.