While the show is still in its infancy, the story has been well developed. The first season of the show has barely tapped into the treasure of the five books in series. The books have three primary plot lines that are constantly interweaving through the books.
The first is the in-fighting of the kingdoms in Westeros after the death of Robert of House Baratheon, but things get tricky when paternity questions begin to rise and the eldest suddenly isn’t the rightful heir and the struggle for power in the kingdoms continues for several books.
Things take a turn when an ancient race of beings called “They Others” return after being gone for thousands of years. The Night’s Watch slowly realize the threat of the others as we watch through the eyes of Jon Snow as he earns respect and power in The Night’s Watch.
The final plot point involves the ambitions of Daenerys Targaryem, the last daughter of the House of Targaryan who has been exiled to Essos. She gains power through the birth of three dragons, a race long thought extinct. She was the throne of Westeros and will do anything to get it.