Dimension X was NBC Radio's pioneering science-fiction anthology, the first to dramatize stories by the genre's leading authors. In "The Lost Race," adapted from Murray Leinster and broadcast May 20, 1950, a shipwrecked space crew stumbles onto the ruins of an ancient, long-dead spacefaring civilization -- only to discover the wreckage hides a deadly secret with the power to destroy the present as it once destroyed the past.