On 21 October, a number of things set in or relevant to the Doctor Who universe were released or published.
- 1967 - Episode four of The Abominable Snowmen was first broadcast on BBC1.
- 1967 - Part three of the TV Comic story The Coming of the Cybermen was first published.
- 1972 - Part ten of the TV Action comic story The Ugrakks was first published.
- 1978 - Part four of The Pirate Planet was first broadcast on BBC1.
- 1989 - Part two of The Incredible Hulk Presents comic story Hunger from the Ends of Time! was first published.
- 1993 - Blood Heat was first published by Virgin Books.
- 1993 - Timeframe: The Illustrated History was first published by Doctor Who Books.
- 2009 - DWDVDF 21 was first published by GE Fabbri Ltd.
- 2010 - The Doctor Who Adventures comic story Cell Shock was first published.
- 2010 - Hell House was first published in TM 24.
- 2015 - The tenth series of Jago and Litefoot was first released by Big Finish.
- 2015 - Part two of Doctor Who: The Tenth Doctor comic story The Singer Not the Song was published.