Production has begun on the second season of Netflix’s 3 Body Problem, and the series is tapping into its Game of Thrones roots for its Season 2 cast. Created by David Benioff, D.B. Weiss, and Alexander Woo, the hit Netflix series is ramping up with casting announcements, although few plot details have been revealed.

3 Body Problem is a sci-fi series based on a book of the same name by Liu Cixin. The show follows the decision of one woman that impacts the world for decades to come. 3 Body Problem is co-created by the creators of Game of Thrones, David Benioff and D. B. Weiss, along with Alexander Woo.

As announced by Netflix today, Game of Thrones alum Alfie Allen has joined the cast of 3 Body Problem season 2 in a mystery role. That’s great news for fans of George R.R. Martin’s world, of course, as now the sophomore installment is basically just a big Thrones reunion—again.