Art student Jess Collins didn't like the work of Escher, but had to read Dimensions of Escher for art history. The Twelfth Doctor told her to never get stuck in an Escher painting because you will feel sick and finding a chemist is "a nightmare". (COMIC: Moving In)
Behind the scenes
The television story Castrovalva is named after the M. C. Escher's print Castrovalva. The titual city of Castrovalva featured confusing spatial geometry seen in M. C. Escher's work. The novelisation was dedicated to M. C. Escher.