Rhea Seehorn in “Pluribus,” now streaming on Apple TV. By SteveJack In an era where dystopian tales flood our screens — zombies shambling through The Walking Dead, surveillance states choking Black Mirror — Vince Gilligan’s Pluribus arrives like a sly whisper in the dark. Premiering on Apple TV just days ago, this sci-fi psychological thriller, starring Rhea Seehorn as the perpetually scowling Carol Sturka, doesn’t bombard us with overt horrors. Instead, it lures us into a world of enforced happiness, where a mysterious extraterrestrial RNA formula, transmitted from deep space, infects humanity through water supplies and petri dishes, transforming billions into a monolithic hive of unrelenting cheer. Carol, one of a handful of those immune — a grieving, cynical writer…