Watch the preview above for the next episode of Doctor Who "Face The Raven."
Doctor Who airs Saturdays on the BBCA starring Peter Capaldi and Jenna Coleman.
The Doctor and Clara, with their old friend Rigsy, find themselves in a magical alien world, hidden on a street in the heart of London. Sheltered within are some of the most fearsome creatures of the universe‚Ä¶ and Ashildr (Maisie Williams)! With a death sentence hanging over their heads, not all of the intruders will get out alive.