They left the flyers at the Ransom House and Tim caught a glimpse of "Mr. Seven" in the lobby. As soon as the flying circus was out of town he'd get on the trail of "Mr. Seven" again and see if he couldn't learn his real identity. There was a story there if he could dig it out. Sunday, the day of the big air show, dawned clear and windless, ideal for the stunt flying and just warm enough to insure the attendance of a large crowd. The first stunts were scheduled for ten o'clock and half an hour before Ace McDowell went aloft to do an outside loop there were more than a thousand cars parked in the roped off spaces around the field with more arriving every minute. Tim's plans for handling the big crowd were working out smoothly and he felt some of the tension slipping from his shoulders. At an early morning conference in the _News_ office with Tommy Larkin and his chief, it had been decided to arrest McDowell when he floated down in his chute after the plane crash. In the meantime, Prentiss would seize the dope in the flyer's plane and they would spring the net from which there would be no escape for McDowell. Tim and Ralph were content to be on the sidelines for they knew the danger in crossing a man like McDowell. The other flyers in the circus were quiet, competent chaps, most of them under thirty and, as far as the narcotics agent could learn, had no connection with McDowell's smuggling activities. The show started with McDowell's stunt flight, which left the crowd gasping and speechless but not so paralyzed but what as a large number rushed for the ticket sellers and bought rides in the other planes. The next stunt program was at one o'clock with Tommy Larkin going aloft with one of the wing walkers, who capered all over the ship in a series of sensational stunts. By early afternoon the crowd had increased to such an extent that the special police estimated more than 15,000 were watching the air show; and the passenger planes were running to capacity on every flight. Prentiss, who had arrived at the field, was remaining out of sight in Carl Hunter's office and once, when McDowell entered, was forced to make a hasty retreat into the washroom. The loudspeakers were blaring with the announcement of the next stunt flight, the crash of the two planes in mid-air. Tim heard the words vaguely. "The greatest air thriller ever performed," the announcer was informing the crowd. "Two costly airplanes, speeding at more than 100 miles an hour, will positively crash head-on at an altitude of 2,000 feet. It's daring, death-defying, breath-taking in its thrills. You'll be glued to your seats when you see these ships hurl towards each other piloted by Ace McDowell and Tommy Larkin, two of the foremost flyers in the nation. They'll go aloft in fifteen minutes. In the meantime, there's time for one more ride in the passenger planes. Let's go, folks."