- You may be looking for the real world television story.
In late 2020, a Doctor Who fan finished an episode of Doctor Who. The final scene ended when a bell was heard, and a female character asked the Doctor what was "Bad Wolf", and he responded by saying it was "the end of the universe". The episode then transitioned into the credits and closing theme. (WC: U.N.I.T. On Call)
Behind the scenes
This is a in-universe counterpart of the real world Doctor Who television story Turn Left that exists within the Doctor's universe. Audio from the episode was heard in U.N.I.T. On Call, which had a Doctor Who fan contact the characters from the TV show, reflecting many fans' idea of asking the Doctor himself for advice about COVID-19.