There’s nothing like a fandom crossover to get a geek’s heart pumping. Just ask Game of Thrones fan favorite Maisie Williams, who is experiencing that outpouring of excitement firsthand through her two-part guest appearance on Doctor Who. “When it was announced that I would be on Doctor Who, everyone lost their minds a little bit,” the actress says matter-of-factly in the behind-the-scenes video above. That’s not an understatement; the news swept through the Internet like an army of White Walkers, rousing both fandoms to intense levels of excitement.
For her two-part adventure with England’s leading Time Lord, Williams has been cast as Viking lass, Ashildre, whose tribe doesn’t know the first thing about defending itself. Enter the Doctor (Peter Capaldi) and Clara (Jenna Coleman), who take it upon themselves to whip these warriors into fighting shape before they’re attacked by an intergalactic enemy. Based on the below clip, it seems that the duo have their work cut out for them, although Ashildre appears to be a quick study. “I hope it lives up to everyone’s expectations,” Williams teases. What’s Gallifreyan for “Valar Morghulis?”
Doctor Who airs Saturdays at 9 p.m. on BBC America