Buck (a typically solid and likable performance by Gil Gerard) and Hawk (a fine Thom Christopher) transport refugees from a planetary disaster to a new home. Buck allows a fugitive woman named Asteria Eleefa (a sympathetic portrayal by the attractive Devon Ericson) to board the Searcher. Eleefa is a member of a harsh mutant race called the Dorians, who hide their faces behind decorated masks. Ruthless Dorian leader Koldar (robustly played by Walker Edmiston) claims that Eleefa is a murderess and demands that she be handed over to him. When Buck refuses to oblige Koldar's demand, the Dorians turn up the temperature on the Searcher. Veteran sci-fi director Jack Arnold, working from an absorbing script by Stephen McPherson, relates the gripping story at a steady pace, maintains an appropriately serious tone throughout, and builds a considerable amount of nerve-wracking tension. The able acting from a bang up cast helps a whole lot, with especially stand-out contributions from Denny Miller as the gallant Saurus, Stuart Nesbet as hot-headed jerk Rand, and Eldon Quick as jolly gambler Chronos. Moreover, this episode delivers a strong and provocative central message on how dire life-threatening situations bring out both the best and worst in people. The titular secret is genuinely surprising. A worthy closer to this fun series.