The Hitchhiker's Guide to the Galaxy a human-like alien writer for the eccentric, electronic travel guide "The Hitchhiker's Guide to the Galaxy", by hitchhiking onto a passing Vogon spacecraft. Following his rescue, Dent explores the galaxy with Prefect and encounters Trillian, another human who had been taken from Earth prior to its destruction by the President of the Galaxy, the two-headed Zaphod Beeblebrox, and the depressed Marvin, the Paranoid Android. Certain narrative details were changed between the various adaptations. The various versions follow the same basic plot but they are in many places mutually contradictory, as Adams rewrote the story substantially for each new adaptation. Throughout
The Hitchhiker's Guide to the Galaxy Tertiary to Hexagonal Phases credits. There was even a cameo role by Adams himself (who had died in 2001) as Agrajag, edited from his BBC audiobook recording of the novel. The original novel was based on a treatment that Adams wrote for an unmade Doctor Who movie, Doctor Who and the Krikketmen. The idea was re-proposed during Tom Baker's tenure in the title role, and again for a potential (but unmade) second television series of "The Hitchhiker's Guide to the Galaxy". Before the final episode was broadcast, BBC Worldwide released the Tertiary Phase on CD, including additional material. A DVD of the series was