"My dear doctor, you must not ask me." For all his elegance and poise, Hubert's complexion was muddy gray under the gray-white hair. "I can scarcely imagine that an inanimate piece of furniture could so affect anybody. Does — does the girl know what has happened?"
"No," snapped Rich. "Do you?"
"I'm beginning to think I do," said Sharpless.
"Yes. And I," agreed Rich. "Somebody switched the daggers. Look here."
Again he knelt beside Arthur's body. With some difficulty, and despite an instinctive protest from everyone, he pulled the weapon out of the wound. Since the heart had stopped pumping, only a little blood followed it.
It was a knife made of very light, very thin steel, with a blade perhaps four inches long. When Rich cleaned it on a handkerchief, they saw that the blade had been painted over a dirty silver-gray. A covering of soft black rubber had been gummed round and over what was presumably a very thin handle.
Moved a little away from the light, it looked very much like the rubber dagger they had seen.
"I thought so," said Rich. "Thick rubber round the handle. And it's pretty dark by that little table. When Mrs. Fane picked it up, she felt the rubber and even her subconscious mind told her it was the same toy dagger she expected it to be. So she didn't hesitate to obey the order." He balanced the knife in his palm. "Even the weight wouldn't tell her any different. Somebody's got a lot to answer for."
"You mean-"
"I mean," said Rich, putting the knife on the floor and getting up, "that I can't be held responsible. Not this time. Someone exchanged a harmless dagger for a real one, and got Mrs. Fane to kill her husband without knowing what she was doing." He pressed a hand to his pink forehead. "It's odd. It's devilish odd. We know the murderer. But we don't know the guilty person."