They were preparing to leave when another flash from Washington came over the radiotelephone. A ship's captain, five hundred miles out on the Pacific, had just reported sighting a great waterspout, accompanied by considerable wave turbulence. "It could have been the spot where the enemy shock waves and our deflector waves met and damped out," Tom commented. "Dr. Miles thinks so, too," the caller said. Soon the sleek Swift jet was arrowing back across the continent. En route, Tom radioed word of his latest triumph to Mr. Swift. As always, he used the automatic scramblers to make sure any enemy eavesdroppers would pick up only static. "Great work, son!" Mr. Swift congratulated Tom. "I was confident you could handle the situation with your Quakelizors." "Thanks, Dad. See you soon." When the jet finally landed at Enterprises and came to a halt on the runway, the control tower operator spoke over the radio. "Harlan Ames would like to see Tom Jr. at the security building. He left word just a few minutes ago." "Roger!" Tom replied. Chow frugally carted off his leftover supplies. Tom and Bud, meanwhile, went by jeep across the plant grounds to security headquarters. Ames greeted the two boys enthusiastically. "Nice going on that earthquake situation, Tom!" he said. "And now I have some more good news. We've just nabbed the man who imitated your father's voice over the phone the other night." "What!" Both boys were excited, and Tom added eagerly, "Who is he?" "An actor at the Shopton summer playhouse." "How did you find out?" Tom asked. "I had a hunch," Ames went on. "If the impersonator wasn't a plant employee at Enterprises, then he had to be a person with a trained voice. That gave me the idea of checking on all actors and station announcers here in the vicinity. It paid off right away. The guy's name is Brent Nolan." "Have you questioned him yet?" Tom asked. "I'm about to," Ames replied. "Radnor just brought him in." The security chief led the way into an adjoining office. A slender, good-looking young man with blond wavy hair was seated on a chair with Phil Radnor on one side of him and a Shopton police officer on the other. The actor was visibly nervous and perspiring. "This is Tom Swift Jr.," Ames told him. "Brent Nolan." Nolan nodded. "Yes, I've seen your picture in the papers many times." The actor tried to force a smile but his face muscles twitched. "I--I seem to have pulled a pretty dumb stunt by faking that phone call from your father. I'm sorry." "What was the reason?" Tom asked. Nolan fingered his wavy blond hair uneasily and swallowed hard. "A man named Professor Runkle paid me to do it." "Professor Runkle?" Tom frowned. The name seemed vaguely familiar.