“Well, Mr. Douglas did not appear. What was he to do next? He left his bicycle and approached the house in the twilight. He found the bridge down and no one about. He took his chance, intending, no doubt, to make some excuse if he met anyone. He met no one. He slipped into the first room that he saw, and concealed himself behind the curtain. Thence he could see the drawbridge go up, and he knew that his only escape was through the moat. He waited until quarter-past eleven, when Mr. Douglas upon his usual nightly round came into the room. He shot him and escaped, as arranged. He was aware that the bicycle would be described by the hotel people and be a clue against him; so he left it there and made his way by some other means to London or to some safe hiding place which he had already arranged. How is that, Mr. Holmes?”

“Well, Mr. Mac, it is very good and very clear so far as it goes. That is your end of the story. My end is that the crime was committed half an hour earlier than reported; that Mrs. Douglas and Barker are both in a conspiracy to conceal something; that they aided the murderer’s escape—or at least that they reached the room before he escaped—and that they fabricated evidence of his escape through the window, whereas in all probability they had themselves let him go by lowering the bridge. That’s my reading of the first half.”

The two detectives shook their heads.

“Well, Mr. Holmes, if this is true, we only tumble out of one mystery into another,” said the London inspector.

“And in some ways a worse one,” added White Mason. “The lady has never been in America in all her life. What possible connection could she have with an American assassin which would cause her to shelter him?”

“I freely admit the difficulties,” said Holmes. “I propose to make a little investigation of my own to-night, and it is just possible that it may contribute something to the common cause.”

“Can we help you, Mr. Holmes?”

“No, no! Darkness and Dr. Watson’s umbrella—my wants are simple. And Ames, the faithful Ames, no doubt he will stretch a point for me. All my lines of thought lead me back invariably to the one basic question—why should an athletic man develop his frame upon so unnatural an instrument as a single dumb-bell?”

It was late that night when Holmes returned from his solitary excursion. We slept in a double-bedded room, which was the best that the little country inn could do for us. I was already asleep when I was partly awakened by his entrance.

“Well, Holmes,” I murmured, “have you found anything out?”