The story of the House Targaryen set 200 years before the events of Game of Thrones (2011). It portrays the beginning of the end of House Targaryen, the events leading up to and covering the Targaryen war of succession, known as the “Dance of the Dragon”.
For an in-depth Hollywood Reporter (opens in new tab) story, the duo revealed that they have an ending in mind and a plan for the show to run a certain number of seasons, which sources saying that three to four seasons are plotted so far.
A short description of the first series:
With both his sons dead and the succession undecided, King Jaehaerys I Targaryen convenes a Great Council for the Westerosi lords to select a future ruler. Jaehaerys’ eldest grandson, Prince Viserys, is chosen over his eldest grandchild, Princess Rhaenys. Nine years into his reign, Viserys organizes a tournament to celebrate Queen Aemma Arryn’s pregnancy, confident she will give birth to a male heir.