The Lonely House by Arthur Gask — Read

One waning night that same week, in the dark minutes that precede the dawn a shadowy figure dropped stealthily over the high wall that surrounded the garden of Dr. Van Steyne. It was clutching to a large bundle, and it alighted just behind a bed of tall artichoke plants. It fell exactly as a dead body would fall, and for quite a long time no sign of any further movement followed. Then softly the tops of the artichokes began to sway, and the face of a man peered out into the dimness from among the leaves.

The man looked round intently on every side and then apparently satisfied that he was quite alone, turned to his bundle and brought out three thin iron rods. These he drove quickly into a bare patch of ground at intervals of a few feet, with each one about a yard distant from the face of the wall. Than he produced a length of canvas and stretched it out in front of the rods, attaching it to the two end ones with small clips of steel. The canvas was painted to match the color of the wall, and it formed a sort of screen about three feet in height and seven feet long. In daylight it would be in full view both of the garage and the house, but so natural was the coloring of the canvas that unless anyone should approach to within a few feet he would not be aware that it was not part of the wall itself.