The Hitchhiker's Guide to the Galaxy President; the depressed robot Marvin the Paranoid Android; and Trillian, formerly known as Tricia McMillan, a woman Arthur once met at a party in Islington and the only other human survivor of Earth's destruction thanks to Beeblebrox' intervention. The first radio series comes from a proposal called "The Ends of the Earth": six self-contained episodes, all ending with Earth's being destroyed in a different way. While writing the first episode, Adams realized that he needed someone on the planet who was an alien to provide some context, and that this alien needed a reason to be there. Adams finally settled
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