"That's right," affirmed the other. "Donald and myself are the only ones with the special keys I designed and constructed. They're made of several alloys and, when inserted in the outside slot, a spectroscope determines whether or not it's the correct key. Even a minor deviation in the alloys would sound an alarm." "And only your assistant and you have possession of the two keys in existence?" A curt nod of the head was his only reply so, in louder tones he demanded, "Then I'd like to see both keys right now, since this is a matter involving security of an Earth secret. One that should've been entrusted to me long ago." * * * * * Stone instantly had his in sight and all eyes swung to Don who was fumbling in his pockets. "I had it earlier in the day," he mumbled in a low voice. At last he had to admit that he didn't have the key. Men sent to investigate his room reported that neither was it there. "Call everyone in the house together immediately," ordered the general; "I thought all along that it was an inside job." "Everyone is here except my daughter," said the scientist. "The only servants we ever had were roboes." "Has anyone seen the girl?" asked the Under-Secretary. There were no answers and a quick but thorough search was fruitless. "Perhaps she went into town," suggested Don. "Without telling anyone?" inquired the general with lifted eyebrows. "Is there a law against it?" snapped back Don. "You seem interested more than usual in springing to her defense," observed the military man with an undertone of triumph that puzzled Don. "I'd trust her further than I would some others," stated Don with an implication that didn't go unnoticed. Rather than the usual rage, however, the general laughed. "You mean that you don't believe that she'd turn traitor and help the roboes obtain the formula?" "Of course not!" the answer was snapped back. "Then what I have to say may interest all of you. Although my proof isn't positive, it comes close enough for me." "Let's get to the point," demanded Don. * * * * * General Adams rocked back on his heels, then with satisfaction stated, "It so happens that I ordered a thorough security check on each of you in this house. You for instance," jutting his chin to indicate Don, "were rather hard to check completely since the orphanage in which your records were kept was completely destroyed by fire. Other than that, everyone was found to be in order." "Thank you," said Don, sarcastically. The interruption was ignored. "Dr. Stone's life was easy to check and, ah, rather routine. Nothing out of the ordinary. His daughter now," he licked his lips; "there's another matter and quite interesting." A quick glance by Don at his employer disclosed that Stone's scientist's face was white. The general had paused for the effect of his words to penetrate then, rather disappointed at the waiting silence, continued.