For a moment Holmes was as surprised as I was. His hand closed tightly around my wrist in his shock. Then he gave a low laugh and put his lips near my ear.

"It is a lovely house," he whispered. "That is the baboon."

I had forgotten the doctor's strange pets. There was a cheetah, too; and it might jump upon our shoulders at any moment. I must admit that I felt much more relaxed when, after doing the same as Holmes and taking off my shoes, I climbed inside the bedroom. My friend very quietly closed the shutters, moved the lamp onto the table. Then he looked around the room. Everything looked the same as we had seen it in the daytime. Then Holmes came up to me and put his hands to my ear. He spoke so gently that it very hard to understand what he was saying:

"Even a little sound would spoil our plans. We must sit without light. He would see it through the ventilator."

I nodded to show Holmes that I had heard him.

"Do not go asleep; your life depends upon it. Keep your pistol ready - we might need it. I will sit on the side of the bed, and you sit in that chair."