New Series Prologue marked the "start" of the ninth series of Doctor Who, although it was not considered an episode proper. It was succeeded by the first episode of the series, The Magician's Apprentice (in-universe).
- You may be looking for the webcast.
It featured the Doctor. By 10 May 2020, the episode was available on BBC iPlayer along with the rest of series 9. (WC: The Zygon Isolation)