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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 premiered on BBC1.
- Part three of the TV Comic story The Coming of the Cybermen was published.
- 1972 - Part ten of the TV Action comic story The Ugrakks was published.
- 1976 - The novelisation of Planet of the Daleks was published by Target Books.
- 1978 - Part four of The Pirate Planet premiered on BBC1.
- 1982 - The novelisation of Logopolis was published by Target Books.
- 1989 - Part two of the Incredible Hulk Presents comic story Hunger from the Ends of Time! was published.
- 1993
- Blood Heat was published by Virgin Books.
- Timeframe: The Illustrated History was published by Doctor Who Books.
- 1999 - DWM 284 was published by Marvel Comics.
- 2002 - The Aztecs was released on Region 2 DVD.
- 2009 - DWDVDF 21 was published by GE Fabbri Ltd.
- 2010
- DWM 427 was published by Panini Comics.
- DWA 189 was published by BBC Magazines.
- 2014 - Toby Hadoke's Who's Round 71 was released online.
- 2015
- Jago & Litefoot: Series Ten was released by Big Finish Productions.
- The Tenth Doctor Year Two #2 was published by Titan Comics.
- TCH 1 was published by Hachette Partworks.
- The Toy was released by Big Finish as the gift for subscribers of The Complete History magazine.
- 2016
- The Torchwood Archive was released by Big Finish.
- Toby Hadoke's Who's Round 190 was released online.
- 2018 - Rosa premiered on BBC One.
- 2021 - Ashenden was released by Big Finish.
- 2024 - The Collection: Season 25 was released.