Game of Thrones became a TV phenomenon in a way that’s hard shows to replicate nowadays. There’s no one reason for its success. Its set pieces blurred the lines between movies and TV. It was wonderfully cast and lushly filmed. But its biggest ace in the hole was its source material: the Song of Ice and Fire books by George R.R. Martin, an as-yet-unfinished fantasy epic full of the sort of granular detail that turns ordinary readers into obsessive superfans.
