"Doctor Who" series 9 is still several months from its autumn release date, but BBC has already posted some behind-the-scenes images of the series in production, as well as several photos revealing some of the new monsters. The Telegraph reported that the first of the featured monsters will appear in episodes 5, "The Girl Who Died," and episode 6," The Woman Who Lived." 

The photos do not reveal the exact setting of the episodes but the news site has reported that production took place at the Cosmeston Medieval Village in the Vale of Glamorgan, the same location used in filming the "Robots of Sherwood" episode of series 8. The medieval setting has been slightly transformed to resemble a Viking village. It will remain closed to the general public until May 2, right after production for the episodes. 

Actor David Schofield, who was one of the runners-up to play Odin in the Marvel Cinematic Universe, will be portraying Odin in the aforementioned episodes. It is unclear if he will be playing the mythological Norse god or if he will be an alien or an imposter. 

The Viking-set episodes will also star Maisie Williams, famous for portraying Arya Stark in "Game of Thrones." It has not been confirmed what her role will be but she will be appearing in the episode alongside another famous guest star, comedian Rufus Hound. 

"It's not possible to say too much about who or what she's playing, but she is going to challenge the Doctor in very unexpected ways," said head writer and executive producer Steven Moffat, as cited by Den of Geek. "This time he might just be out of his depth, and we know Maisie is going to give him exactly the right sort of hell." 

Both episodes will be helmed by Ed Bazalgette. Bazalgette was popular during the 1980s as the guitarist for the band "The Vapors." They were considered a one-hit wonder with just one song that topped the charts, "Turning Japanese." He has since moved on to direct several BBC documentaries as well as 2014's "Poldark."