Next, all Madolin's classmates at the Technicum, the operators of her teach-communicators, and members of other classes with whom it was learned she had been on familiar terms, were subjected to an intensive electronic questioning. (Several of these were themselves discovered to be tainted with Naturism, and were interned with the rest.) One of the tenets of Naturism is a return to the outworn system of monogamy, and the questioning was directed particularly to the possibility that Madolin had formed half of one of the notorious Naturist "steady couples," who often associate without or before actual mating. But day after day the investigators came up with not the slightest usable lead. Please do not think I am underrating Fedpol. Nothing could have been more thorough than the investigation they undertook. But this turned out in the end to be a case which by its very nature obfuscated the normal methods of criminological science. Fedpol itself has acknowledged this, by its formation in recent months of the Affiliated Assistance Corps, made up of amateurs who volunteer for the detection of what are now called Class X crimes--those so far off the beaten path that professionals are helpless before them. For it was an amateur who solved Madolin Akkra's murder--her own little sister. When Margret Akkra reaches the working age of 25 she will be offered a paid post as Newyork Area Co-ordinator of the AAC. * * * * * Left alone by her father's internment, Margret began to devote her whole time out of school hours to the pursuit of the person or persons who had killed her sister. She had told Kazazian all she actually knew; but that was only her starting-point. Though she herself, as she had told the Inspector, believed that the murder might be traced to Madolin's connection with the Naturist (and though she probably at least suspected her father to be involved with them also), she did not confine herself to that theory, as the Fedpol, with its scientific training, was obliged to do. Concealed under a false floor in her father's bedroom--mute evidence of his Naturist affiliation--she found a cache of printed books--heirlooms which should long ago have been presented to a museum for consultation by scholars only. They dated back to the 20th century, and were of the variety then known as "mystery stories." Margret of course could not read them. But she remembered now, with revulsion, how, when she and Madolin were small children, their mother had sometimes (with windows closed and the videophone turned off) amused them by telling them ancient myths and legends that by their very nature Margret now realized must have come from these contraband books.