The Hitchhiker's Guide to the Galaxy is a science fiction comedy series created by Douglas Adams. It was originally a radio comedy broadcast on BBC Radio 4 in 1978, followed by a "trilogy" of five books beginning in 1979.
- The second book in the series, The Restaurant at the End of the Universe, was the inspiration for the title of the Muppet Babies episode "The Air Conditioner at the End of the Galaxy."
- In the Farscape episode "Unrealized Reality," Arthur Dent is one of several sci-fi/fantasy heroes mentioned by John Crichton: "But I am not Kirk, Spock, Luke, Buck, Flash or Arthur frelling Dent. I'm Dorothy Gale from Kansas."
- The making of The Muppets documentary Scratching the Surface is told in a style that references the radio and TV series. A British narrator (ala "the voice of the Book" in both radio and TV versions) tells the story of the making of The Muppets with over-explained sidebars featuring comedic graphs and faux-scientific explanations for several parts of the story (a visual element utilized in the TV series).
- BBC Radio launched a new radio series in 2004, adapting the last three of Adams' books, in three "phases." In the six part "Tertiary Phase" series, adapting Life, the Universe, and Everything, the announcer's closing gag for the October 19, 2004 broadcast (episode five), referenced the sponsorship closings on Sesame Street: "This week's program was brought to you by the letters F, Gamma, and the hexadecimal number 3 cosine D bracket to the power of 8... sorry, 9... no, 8.... actually, can I get back to you?"
Many people who have appeared in Muppet/Henson productions have connections to The Hitchhiker's Guide to the Galaxy radio and TV series.
- John Baddeley played Bird Two and the Footwarrior in the second radio series.
- Jim Broadbent played Vroomfondel and Shooty in the first radio series.
- Ken Campbell played Poodoo in the second radio series.
- Peter Davison played the Dish of the Day in the TV series.
- Stephen Fry played Murray Bost-Henson in the fourth radio series
- Michael Gahr played the second computer programmer in the German radio series (1982).
- Michael Habeck played Shooty in the German radio series (1982).
- Peter Hawkins played Frankie Mouse in the first radio series.
- Wolfgang Hess played Mr. Prosser in the German radio series (1982).
- Jane Horrocks played Fenchurch in the fourth radio series.
- Chris Langham played Prak in the third radio series.
- Joanna Lumley played the Woman with the Sydney Opera House Head in the third radio series.
- Miriam Margolyes played Smelly Photocopier Woman in the fifth radio series.
- Frank Middlemass played the captain of the B Ark in The Hitch-Hiker's Guide To The Galaxy Part Two: The Restaurant At The End Of The Universe (1980 album version)
- Bill Paterson played Arcturan Number One in the second radio series, and Rob McKenna in the fourth.
- Jonathan Pryce played Autopilot in the second radio series, and Zarniwoop in the second and fifth.
- Griff Rhys Jones played Old Thrashbarg in the fifth radio series.
- Bernd Stephan played the Magrathean PA voice in the German radio series (1982).
- Richard Vernon played Slartibartfast in the first radio series and the TV series.