The fugitives spot humans singing near the edge of a cliff overlooking the 'Beach of Time', which Galen recognizes as the rite of taboo purification. The Beach of Time is filled with taboo artifacts that must be destroyed so the sand can be used for construction. A woman named Nebia is about to be fed to sharks - "purified" - for violating the taboo. Virdon and Burke rescue Nebia and toss a dummy into the sea. The fugitives and Nebia hide in a cave, where she says she's been a slave her whole life. She shows them a handheld radio she found, which broadcasts an invitation to survivors of the war to take refuge at the East Coast Scientific Center's bomb shelter. Virdon dismantles the radio to build a goniometric radiometer but needs additional parts. Galen poses as a slave-tamer from the vil