Carnival Row is the exact type of show that is going to populate a post-Game of Thrones world for years to come. Co-creators Travis Beacham and René Echevarria have been trying to bring this thing to life for years—at one point it existed only as Beacham's feature-film spec A Murder on Carnival Row, in an entirely different life Guillermo del Toro was attached to direct the series—but the fact it's finally made its way to air now seems auspicious. Networks are racing to fill the void left by the biggest show of all …