When Game of Thrones first made its debut on HBO back in 2011, the network knew the book series already had a large, devoted fan base and hoped to build on that audience. What the HBO didnt know, but were extremely pleased with, was just how quickly the series would become the networks and most talked about show on television, averaging more than 18 million viewers per episode by its third season. The series, based on the Song of Ice and Fire series of fantasy novels by George RR Martin, is...