Courtney spoke into a vast silence.
"A short ladder," he said.
"Right. A short ladder.
"Y'see, my fatheads, all this guff and hoo-ha about a four-foot unmarked flower-bed, and dust on the window-sills, doesn't mean a curse. Why should either trouble you — if all you've got to do is prop up the ladder on a concrete drive, across the flower-bed, and rest it on the outer edge of the window-sill?
"All your assumptions, you understand, were based on the belief that somebody must have climbed through the window and into the room. But, of course, nobody ever did get into the room at all. It wasn't necessary."
Again there was a silence.
"But the time taken to do all this!" protested Sharpless.
H.M. emitted a ghoulish chuckle. "I sort of thought somebody would mention that. I got here—" he held it up—"a stop-watch. You, son, go out into the dining room now. When you hear somebody shout 'Go!' run through the same motions as Hubert. You'll find the ladder outside. Prop it up, and stick your head through the window."
H.M. handed the stop-watch to Courtney as Sharpless strode out of the room.
"Clock him," H.M. instructed.