It starts with the writing - which is really, really good. And the production values are phenomenal. HBO and Sky have spent money on it, and you get what you pay for. This has money put into it properly - not lavish amounts - but as each season is successful, they maintain the money that's being spent to maintain the quality.
My screenplays are very detailed. The reason they're detailed. . . you have to think on your feet. You have to be ready to change because there are no such things as ideal conditions.