Matildus

Continuing their attempts to decipher the symbol left on the doors of the TARDIS, the Twelfth Doctor and Bill Potts travel to the Renath Archive, an enormous library run by a woman called Matildus Galathea, underneath the spaceport of Cornucopia. Upon landing, the Doctor is immediately confronted by Matildus for losing a variety of books, but she begrudgingly accepts his replacements.