Reality TV is, at its core, about letting viewers revel in the bad decision-making of others: those who speak without thinking, who backstab, who have sex without condoms, who cheat. Frustratingly, though, reality shows—to which I am unapologetically addicted—tend to reward bad behavior, by giving its villains notoriety, spinoffs, opportunities to endorse weight-loss products, a nice sideline in paid interviews with supermarket tabloids, and other D-list rewards.Locked Up Abroad is different. The National Geographic show, the sixth season...