While all episodes were in colour, the pilot had originally survived only in black-and-white as a film transfer from the original colour source; however, it was restored into colour using the chroma dots computer colour restoration technique and was aired on BBC Two on 1 January 2010.
Despite all episodes being in color, the pilot initially existed only in black-and-white as a film transfer from its original color source. It was later restored to color through the chroma dots computer color restoration method and broadcasted on BBC Two on January 1, 2010.