The Hitchhiker's Guide to the Galaxy: The Original Radio Scripts contains a new introduction by Geoffrey Perkins, and newly researched material by M. J. Simpson, including a transcript of "The Lost Hitchhiker Sketch." The sketch was an interview with Simon Jones in character as Arthur Dent, conducted by Sheila Steafel on her show "Steafel Plus" in 1982, written entirely by Adams. The sketch can be heard in the "Douglas Adams at the BBC" CD collection. The book now contains transcripts of all Hitchhikers radio sketches, barring a sketch for Marvin that Adams wrote for the BBC Radio 1 show Studio B15 to promote the television version of the serial, which
The Hitchhiker's Guide to the Galaxy Tertiary to Hexagonal Phases else entirely. The Hitchhiker's Guide to the Galaxy: Tertiary Phase, based on "Life, the Universe and Everything", ran on BBC Radio 4 from Tuesday 21 September to 26 October 2004, with repeats on the following Thursdays. Episodes were subtitled "Fit the Thirteenth" through "Fit the Eighteenth". The third novel was adapted by Dirk Maggs, John Langdon and Bruce Hyman following instructions left by Adams. Most of the original radio series cast returned, with the exception of three, due to their deaths: Richard Vernon (died 1997) as Slartibartfast, replaced by Richard Griffiths; Peter Jones (died 2000), replaced by his friend William