"I know!" the scientist puffed. "Stop! Stay right where you are." He jabbed a finger emphatically downward to anchor the couple in the exact spot they occupied. "Don't talk! Don't say a word--until I get back." Fairchild returned after a time, unhurried and completely at ease. He did not need to ask the shaken couple if they had seen what had occurred. It was plainly evident that they had. "But--but, Doctor--" Ryder began. "Keep still! Don't talk at all!" Fairchild ordered brusquely. Then, in an ordinary conversational tone, he went on: "Until we have investigated this extraordinary occurrence thoroughly--sifted it to the bottom--the probability of spying cannot be disregarded. As the only eye-witnesses to what actually happened, your reports will be exceedingly valuable. But I do not want to hear a word until we are in a place which I am sure beyond peradventure is proof against any and all spy-rays. Do you understand?" "Oh yes, I understand." "Pull yourselves together, then. Act unconcerned, casual--particularly when we get to the Administration Building. Talk about the weather, or, better yet, about the honeymoon you are going to take on Chickladoria." Thus it was that there was nothing noticeably abnormal about the group of three which strolled into the office building and entered a private automatic elevator. The conveyance, however, went down instead of up. "I am taking you to my private laboratory, not to my office," Fairchild replied to Ryder's unspoken question. "Frankly, young folks, I am a scared--a badly scared man." This statement, so true and yet so misleading, resolved thoroughly the young engineer's inchoate doubts. Entirely unsuspectingly the couple accompanied the Senior Radiationist along the grim corridor. They paused as he unlocked and swung open a door of thick metal; they stepped unquestioningly into the room in response to his gestured invitation. He did not, however, follow them. Instead, he swung shut the heavy slab, whose closing cut off completely the filing clerk's piercing scream of fear. "Cut out that noise!" came raspingly from a speaker in the steel ceiling of the small room--a room which was very evidently not Doctor Fairchild's private laboratory. "It won't do you any good. You're sound-proofed. Talk all you please, but any more of that yelling and I'll have to put you out of your misery." "But Mr. Graves, I thought--Dr. Fairchild told us--we were to report on that--" Ryder's words came confusedly from the maze of his surprise. "You're to report on nothing. You saw too much and know too much, that's all." "Oh, so _that's_ it." Ryder's mind reeled as some part of the actual significance of what he had seen struck home. "But listen, Graves. Jackie didn't see anything. She had her eyes shut all the time, and doesn't know anything. You don't want the murder of such a girl as she is on your mind, I know. Let her go and she'll never say a word. We'll both swear to that. Or you could--"