“I am naturally observant, as you may have remarked, Mr. Holmes, and I soon had a pretty good plan of the whole house in my head. There was one wing, however, which appeared not to be inhabited at all. A door which faced that which led into the quarters of the Tollers opened into this suite, but it was invariably locked. One day, however, as I ascended the stair, I met Mr. Rucastle coming out through this door, his keys in his hand, and a look on his face which made him a very different person to the round, jovial man to whom I was accustomed. His cheeks were red, his brow was all crinkled with anger, and the veins stood out at his temples with passion. He locked the door and hurried past me without a word or a look.

“This aroused my curiosity; so when I went out for a walk in the grounds with my charge, I strolled round to the side from which I could see the windows of this part of the house. There were four of them in a row, three of which were simply dirty, while the fourth was shuttered up. They were evidently all deserted. As I strolled up and down, glancing at them occasionally, Mr. Rucastle came out to me, looking as merry and jovial as ever.

“ ‘Ah!’ said he, ‘you must not think me rude if I passed you without a word, my dear young lady. I was preoccupied with business matters.’

“I assured him that I was not offended. ‘By the way,’ said I, ‘you seem to have quite a suite of spare rooms up there, and one of them has the shutters up.’

“He looked surprised and, as it seemed to me, a little startled at my remark.

“ ‘Photography is one of my hobbies,’ said he. ‘I have made my dark room up there. But, dear me! what an observant young lady we have come upon. Who would have believed it? Who would have ever believed it?’ He spoke in a jesting tone, but there was no jest in his eyes as he looked at me. I read suspicion there and annoyance, but no jest.

“Well, Mr. Holmes, from the moment that I understood that there was something about that suite of rooms which I was not to know, I was all on fire to go over them. It was not mere curiosity, though I have my share of that. It was more a feeling of duty - a feeling that some good might come from my penetrating to this place. They talk of woman’s instinct; perhaps it was woman’s instinct which gave me that feeling. At any rate, it was there, and I was keenly on the lookout for any chance to pass the forbidden door.

“It was only yesterday that the chance came. I may tell you that, besides Mr. Rucastle, both Toller and his wife find something to do in these deserted rooms, and I once saw him carrying a large black linen bag with him through the door. Recently he has been drinking hard, and yesterday evening he was very drunk; and when I came upstairs there was the key in the door. I have no doubt at all that he had left it there. Mr. and Mrs. Rucastle were both downstairs, and the child was with them, so that I had an admirable opportunity. I turned the key gently in the lock, opened the door, and slipped through.