After the third day the blackboard had been erased and the classroom released for its regular classes. Police enthusiasm dropped to the norm of what they called legwork. Finding out who the missing man's acquaintances and friends were, calling on them and talking to them in the hopes of picking up something they could go on. They passed Martin Grant by because they had heard from him in their initial work. In fact, he had been a little too present for their tastes. After ten days they dropped the case from the active blotter. The University, seeing that there was little likelihood of having to shell out the reward money, increased it to five hundred dollars. But Martin Grant continued to ponder over a conversation he himself had had with John Henderson during a dinner six weeks to the day before his old friend had vanished. He remembered his own words... * * * * * "... and so you see, John, by following this trail, I've arrived at a theory that has to do with the basic nature of the universe--of all reality. Yet things don't behave as they would if my theory were operating." John Henderson frowned into space, disturbed. Visibly disturbed. Martin watched him with a twinkle in his eyes. "You must have gone off the track on it somewhere, Martin," John said suddenly, as though trying more to convince himself than his listener. Martin shook his head with slow positiveness. "You followed every step. We spent four hours on it." He took pity on his friend. "Don't let it bother you. I regard it as just an intellectual curiosity. I've included it in my next book on that basis." A new voice broke in. "What is it, Dad? One of your ten-thousand-word shaggy dog jokes?" This from Fred Grant, 16, student in the senior grade at the Hortense Bartholemew High School, and an only child of Martin Grant. "A little more respect toward your father," Martin said with much sternness. "Yes, Father." "It was my _theory_." John Henderson said, "But, Martin, I don't know what to think now. Of course there must be some fallacy that I've missed. The way things stand though, I--" He chuckled uncomfortably. "I begin to doubt myself. I can't quite classify it as an intellectual curiosity." "What else can you do with it?" Martin said. "I know your trouble. It's a common one. You have a tendency to believe things or disbelieve them. Now you've been presented with something your intellect demands that you believe, while your experience shouts, 'lie'." "Is Fred able to understand it?" John asked, smiling at the youngster with fond and unconscious condescension. "Not yet," Fred smiled. "I'm still in high school." "And if you don't want to flunk out you'd better be off to bed at once," Martin told him. "Yes, Father. Good night, Dr. Henderson."