It was half-past eleven on the night of Wednesday, April 14th, when the well-known red limousine of Mr. Maverick Narkom, superintendent of Scotland Yard, came abruptly to the head of Mulberry Lane, which, as you may possibly know, is a narrow road skirting one of the loneliest and wildest portions of Wimbledon Common. Lennard, the chauffeur, put on the brake with such suddenness that the car seemed actually to rise from the earth, performed a sort of buzzing and snorting semicircle, and all but collided with the rear wall of Wuthering Grange before coming to a halt in the narrow road space which lay between that wall and the tree-fringed edge of the great Common.