We must not let the doctor see us. Until tonight, then.”

Holmes and I went to the inn to wait. We had a room from which we could see Stoke Moran. At about seven we saw Dr. Roylott get home. We knew it was he. We could hear him yelling at the boy who opened the gates.

At about nine o’clock the lights in the house went out. All was dark. Two hours passed. Then we saw a light flash out from the middle window.

“That’s our signal,” said Holmes. A moment later we were out on the dark road. A cold wind blew in our faces. We made our way over the old stone wall and across the yard. We got in through the window of Julia’s room.

We had to be very quiet. The smallest sound might wake Dr. Roylott next door. We did not dare have a light, either. Roylott might see it through the air vent. So as soon as we were safe, we blew out the candle. I had my gun ready.

“Do not go to sleep,” whispered Holmes. “You may lose your life if you do.”

How shall I ever forget that long wait? I could not hear a sound. We were in the dark. We heard the clock strike twelve. Then one. Then two. Then three.

Suddenly I saw a flash of light. It had come through the air vent! Then all was quiet again.

In a moment I heard another sound. It was a soft hiss. It sounded like steam coming out of a kettle. Holmes jumped up.