Poirot looked across at once to the window which gave upon a gravelled terrace.
"The window, it was unlatched?" he asked.
"That's the whole point, of course. When the doctor left this room, he merely closed the door behind him. The next morning it was found locked. Who locked it? Mr. Paynter? Ah Ling declares that the window was closed and bolted. Dr. Quentin, on the other hand, has an impression that it was closed, but not fastened, but he won't swear either way. If he could, it would make a great difference. If the man was murdered, some one entered the room either through the door or the window—if through the door, it was an inside job; if through the window, it might have been any one. First thing when they had broken the door down, they flung the window open, and the housemaid who did it thinks that it wasn't fastened, but she's a precious bad witness—will remember anything you ask her to!"
"What about the key?"
"There you are again. It was on the floor among the wreckage of the door. Might have fallen from the keyhole, might have been dropped there by one of the people who entered, might have been slipped underneath the door from the outside."
"In fact everything is 'might have been'?"
"You've hit it, Moosior Poirot. That's just what it is."
Poirot was looking round him, frowning unhappily.
"I cannot see light," he murmured. "Just now—-yes, I got a gleam, but now all is darkness once more. I have not the clue—the motive."
"Young Gerald Paynter had a pretty good motive," remarked Japp grimly. "He's been wild enough in his time, I can tell you. And extravagant. You know what artists are, too—no morals at all."