From NetFlix:

When a power vacuum emerges in the mythical land of Westeros following mighty King Robert’s death, several noble families, including the Starks, Lannisters and Baratheons, wage war against each other for control of the vacant Iron Throne. Full of political and sexual intrigue, this fantasy series, based on George R.R. Martin’s “A Song of Ice and Fire” novels, also chronicles the rise of an ancient evil, which threatens the entire kingdom.

UPDATE: April 2016

Only 5 seasons are available at this time.  Season 6 has not yet appeared.   If you don’t mind violence, nudity, crude language, cruelty, etc. then this series continues to be spellbinding. By this time Peter Dinklage has made his fame with his portrayal of Tyrion Lannister. And those dragons are really cool.

If you want details just go to Wikipedia.

Season One consists of 5 disks. You might not like this series unless you enjoy such guilty pleasures as intrigue, nudity, fantasy, sex, revenge, and violence. In other words: What’s not to like?

Among the huge cast you will notice:

• Sean Bean (as Eddard Stark) was Boromir in “Lord of the Rings”.
• Peter Dinklage plays Tyrion Lannister who throughout the story calls himself a dwarf. You might remember him from Death at a Funeral (2007) or The Station Agent (2003)
• Iain Glen (as Ser Jorah Mormont) appears in many British productions. He was the wonderful villain Vaughan Edwards in part of MI-5

Production values are excellent. Note especially the opening of each episode in which the camera pans an abstract model of the entire mythical kingdom.

If this kind of fantasy is your cup of tea, then I would call “Game of Thrones” as DO NOT MISS!