It's been a great week for Game of Thrones fans. After casting Academy Award nominee Naomi Watts in the lead for the first Game of Thrones prequel, the HBO pilot got an official title (The Long Night) and now even has a male cast member.

According to The Hollywood Reporter, British actor Josh Whitehouse will join Watts in the pilot, which will more than likely be ordered to series by the premium network because it's a Game of Thrones prequel and HBO will want to stay in the Westeros business. Details on who Whitehouse is playing are naturally being kept under wraps for now, but he has a "key role" that is not the male lead. Whitehouse currently co-stars in the PBS Masterpiece series Poldark.

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The potential series takes place thousands of years before the events of Game of Thrones. That time period in Westeros is known as the Age of Heroes and is populated by familiar names like Bran the Builder and Lann the Clever. The new series was created by Jane Goldman and A Song of Ice and Fire author George R.R. Martin. Goldman also penned the pilot and will serve as showrunner if HBO makes the pickup.

The Long Night is one of four potential Game of Thrones spin-offs that HBO has in the works and the first to actually go into production. Each of the series will take place in a different time period of Westeros, which limits the possibility for crossover but will greatly expand the mythos of the Game of Thrones universe.

Production on the final season of Game of Thrones wrapped this summer. The last six episodes are expected to premiere in the first half of 2019.

Josh Whitehouse, <em>Poldark</em>Josh Whitehouse, Poldark