The smile was strained, and Rick thought he knew why. He had seen his father face great physical danger without losing a bit of his composure. But the insidious weapon that could read all reason out of minds was far more horrible to a man like Hartson Brant than any physical danger could be. Bullets, knives, and clubs may leave bad wounds, or they may kill. But what chance is there for anyone with a damaged brain? Scotty looked at his watch and held it up for Rick to see. Nearly an hour and three-quarters had passed since the call to Steve. Rick gestured to Scotty and urged, "Hurry, Dad." "I'm ready." The scientist closed his bag. Barby got to it first and lugged it down the stairs, refusing Scotty's offer of help. The boys went to their stations while the others waited on the porch. Rick checked to be sure he had matches, then worried because a wind had sprung up. Suppose it blew his match out? He was about to go borrow his father's lighter when he heard the far-off drone of a plane. There wasn't time now! He held the matches in his hand, ready. The drone grew nearer, rising to a high whine. The plane was diving! Suddenly it was overhead and gone with a crash of sound. Rick saw its lights head out to sea. Mike was making a tight turn to come in for a landing. Rick's lips formed the words. "Now, Scotty! Now!" And, as though he had heard, Scotty threw the switch. Lights flared on the lab roof, outlining it clearly. Rick struck a match and held it to the saturated cord of rags. Flaming gasoline ran along the cord in both directions, ran up the sides of the cans. There was a loud whoosh of exploding gasoline, and both cans were ablaze. Rick ran away from the heat. Mike came in low and fast over the lab roof and slapped the plane down on the turf. In a moment he applied the brakes and the wheels whined their protest as they dug up grass. Then the plane was rolling to a stop directly in front of the house. The pilot jumped out and called, "Hello, gang! Come on, sir. No time to waste!" Hartson Brant kissed Mrs. Brant and the girls, found time to pat Rick's shoulder, and climbed in. Rick took the suitcase from Barby and handed it to the scientist. The door closed and the plane was whirling, catching them in its prop blast. Mike taxied back fast to the laboratory, turned the plane and revved up, holding on the brakes. Rick saw Scotty emerge from the lab building and go right back in again as the prop wash caught him. Then the plane was rolling ... and lifting. Mike skimmed low over the burning trash cans, banked out to sea, and was gone. Rick felt a sob rising in his throat and resolutely squelched it. He walked to the burning cans and dropped covers on them. Scotty cut the lights on the lab building. Had they made it? They wouldn't know. Not until Steve reported that the scientist was safe. On the porch, Barby asked, "How soon will we know?"