He leaped back in surprise⁠—passing through the space formerly occupied by Di Costa. Gone⁠—while he had been studying the note! Leaning over the rail he had a quick glimpse of the stiff figure entering the Central Park Skyport. Cursing himself for his stupidity, Brent changed lanes and raced back to the Skyport entrance.

His luck still held. Di Costa was on the outgoing air cab line. It would take him at least ten minutes to get a cab this time of day. With a little speed and a few greased palms Brent could rent a Fly-Your-Own before the other man was airborne.

Shortly after, the orange and black cab flashed up from the takeoff circle followed closely by Brent’s blue helio. The two aircraft flew north and vanished in the distance over the Hudson.

The air cab stayed at the 10,000 foot level. Brent cruised at 8,000, lagging slightly behind, keeping in the blind spot of the other ship. The entire affair was moving too fast for his peace of mind. He had the feeling that he was no longer a free agent, that he was being pushed into things before he decided for himself.

He suddenly felt elated. The strange symbol on the note, the note that disappeared in such an inexplicable fashion, proved the existence of alien hidden forces. Every mile that rushed under his plane brought him closer to the answer. He didn’t fear death⁠—it was no longer a stranger to him. The moments of time left to him might be made more satisfactory if he ferreted out this secret. He smiled to himself.

Fifteen minutes later the two ships grounded at the Municipal Skyport in Poughkeepsie. Brent parked the ship and followed his quarry down to the street level. Except for a certain stiffness in his movements, Di Costa seemed normal. He walked quickly and turned into an office building before Brent could catch up with him.