House of the Dragon, a Game of Thrones prequel will air August 21 on HBO. It's based on the book, Fire and Blood, by George R. R. Martin and is set in Westeros 200 years before the original Game of Thrones series.

If you watched all of the Game of Thrones series, this one should be an interesting addition to your viewing pleasure.

I've read about 1/2 of the book so far, and it's good, but doesn't quite live up to the original Game of Thrones series of books. Still, it's worth reading and seeing.

https://en.wikipedia.org/wiki/House_of_the_Dragon