Robot specialist Derec Avery and Calvin Institute attache Ariel Burgess - last seen in Asimov's Aurora by Mark Tiedemann - return in an all-new adventure. A human has been murdered, and all the clues point to a robot as the killer. But how can that be, when robots are programmed to never bring harm to humans? Derec and Ariel must find the murderer - before they become the next victims...