“It is the wooden-legged man.”

“Quite so. But there has been someone else⁠—a very able and efficient ally. Could you scale that wall, doctor?”

I looked out of the open window. The moon still shone brightly on that angle of the house. We were a good sixty feet from the ground, and, look where I would, I could see no foothold, nor as much as a crevice in the brickwork.

“It is absolutely impossible,” I answered.