British writer Jed Mercurio builds television shows the way the Cenobites build puzzle boxes in the Hellraiser movies. Get too close to one, and its intricate mechanism shoots its hooks into you, pulling you through a portal into a gyre of suspense from which there’s no escape. —Mike Hale, New York Times One of the precarious aspects of reviewing a thrilling book, film or series, is the danger of publishing “spoilers”—that is, giving away parts of the plot that are best left to be discovered by readers or viewers during their own first experience of the work. The new…