BBC Film and Videotape Library

More commonly known as the BBC Archives, the BBC Film and Videotape Library was an entity created in the late 1970s in response to the realisation that much early television material was missing. Doctor Who was just one of many series to have episodes missing from the BBC,. Others including Dad's Army and Out of the Unknown.

An early omission from the run of Doctor Who episodes was The Feast of Steven, (Episode 7 of The Daleks' Master Plan which, while recorded on 405 videotape like every other William Hartnell episode, was erased a short time after being made; it was not telerecorded like the other episodes of the series because, given its seasonal nature, it did not fit well into continuity.