"Last night, or rather about two o'clock this morning, came one of those untimely summonses of which I have made mention above. I was aroused by Cleon's tapping on the wall that divides our bedrooms. I shuffled into a few clothes, anathematizing M. Platzoff and the whole business as I did so, and then hurried into Cleon's room. As I expected, M. Platzoff's bell had just rung, and it was requisite that I should go and ascertain what was wanted. I took my pass-key and went. I passed first through the smoking-room, next through the dressing-room, and so into the bedroom, which, to my intense astonishment, I found lighted up with a pair of wax candles, although I had left it in utter darkness barely a couple of hours before. What added to my surprise was the fact that the door between the bedroom and the library was open, and that the latter apartment was also lighted up. Having noted these things with a first intuitive glance round, my second glance went to the bed in search of M. Platzoff. He was not on it. On passing round the foot of the bed, I found him lying with his face on the floor. I lifted him up and saw at once that he was in some sort of a fit. I was frightened, but did not lose my presence of mind. I had several times carried him out of the smoking-room when he was in one of his opium trances, and I had no difficulty now in lifting him up, and laying him on the bed. As I turned round with the body in my arms I saw something reflected in a large mirror opposite that nearly caused me to drop M. Platzoff to the ground. What I saw was the reflection from the lighted-up library of an oblong opening like a doorway in the bookshelves with which its walls were lined--an opening which, had it been there, I should hardly have missed noticing before, although I had not been above three or four times in the room. As soon as I had laid the unconscious Russian on his bed, I stole on tip-toe into the library. I had not been mistaken. There _was_ an opening in the wall formed by the sinking into a deep recess of a portion of the bookcase. In the recess thus formed was an iron door, now shut. As I looked, this question, without any consciousness on my own part, was put to me: _Can this be the entrance to some secret room in which the Diamond is hidden?_