Eventually, Sheppard determines that a powerful radio transmitter and receiver were secretly built into NOVAC during its construction in Switzerland, without the knowledge or consent of its designer, Dr. Zeitman. An enemy robot plane, whose fiberglass body does not register on radar, has been flying overhead, beaming precisely focused, ultra-high-frequency radio signals into the complex to control NOVAC's every function. The computer, in turn, controls Gog and Magog, two huge mobile robots with multiple arms, powerful gripping tools, and other implements.
