* * * * * Two weeks passed with no new developments in the "Invisible Death" case except for the arrival of a letter demanding $1,000,000 and threatening the life of Perkins Ferguson if the demand was ignored. It was ignored, and only served to spur Lees and his detectives on to decisive action. They decided to rush the Jouret house and kidnap Jouret with the idea of holding him until he agreed to explain the presence of the number nine shoes buried back of his house. A low moon hung over the poplars when Lees rang the Jouret front door bell. One detective was guarding a side door and the other a back door. Suddenly Jouret was seen to jump from a second-story window. As he did, a car driven by one of his Porto Ricans came along the drive and he leaped into it. Lees, first to see Jouret, called his detectives. They came running. Their car was waiting in the road. The Porto Rican was seen to jump from the Jouret car just as it started south towards New York. Lees took up the race. Both cars had plenty of power, but the Jouret car suddenly disappeared as a low humming noise began to break the stillness of the night. One of the detectives was at the wheel. Lees, as usual, was giving orders: "Keep close to that hum. Never mind that you cannot _see_ the car. It is there all right. If you can gain on it enough, drive right into it." "Righto!" shouted the detective. "We're wise to him now." The humming noise was taking on speed with every second. So was Lees' car. Soon Lees' car was making sixty miles an hour with the hum just ahead and barely audible. Past traffic lights, over bridges and grade crossings the mad chase of the phantom continued. Wildly racing through the night, missing other cars by a breath, the big, visible auto continued its pursuit of--what? Careening, Lees' car rounded a curve, and, above the hum just ahead, they heard the shouted curses of their quarry. But he could not be seen. Lees could only see the road marked by his lights. Mile after mile the wild, uncanny chase of the phantom continued. * * * * * Soon the lights of New York could be seen in the distance. The cars were forced to slow down somewhat. Suddenly there was a thundering crash ahead. A car was twisted in a mass of tangled wreckage. Feminine and masculine shrieks blended as Lees' car piled up on the wrecked heap. A third car, becoming suddenly visible, rolled over and brought up at the edge of the road. From this car emerged the limping, cursing form of Jouret. From the wreckage three painfully injured young men dragged and tore themselves. Then they leaped--ignoring their hurts--at the limping figure. The fight was on. Jouret was heavy and powerful and proved an obstinate fighter, for he knew he was fighting for his life. He bit and clawed. He kicked with one uninjured leg and butted with his massive head.