Professor Coleman presents a special machine for checking loyalty - the Electronic Suspicious Idea Detector, abbreviated as OEDIP. An impartial machine will notice and score everything: emotions and body temperature, sweaty palms and changes in voice timbre. Moreover, based on the results of the calculation, the machine will pronounce a verdict, the verdict is final and not subject to appeal. At the end of the conference of the Society of Electronic Engineers, a farewell banquet was given in the large halls of the Imperial Hotel, and after the banquet the professor unexpectedly found himself in the Oedipus cabin...