An ordinary, anxious Englishman whose house is demolished to make way for a bypass shortly before Earth is destroyed for a similar galactic reason. Still wearing his dressing gown and pajamas, he is ill-equipped for space travel and constantly struggles to comprehend the absurdity of the universe.

Arthur’s eccentric friend who reveals himself to be an alien researcher for the Hitchhiker's Guide to the Galaxy. He has been stranded on Earth for fifteen years while posing as an out-of-work actor and serves as Arthur's knowledgeable, if somewhat erratic, guide to survival in space.

The narcissistic, irresponsible, and two-headed President of the Imperial Galactic Government. He steals the prototype starship Heart of Gold for reasons even he doesn't fully understand, driven by a desire for fame and a mysterious locked section of his own brain.

A brilliant mathematician and astrophysicist from Earth whom Arthur once met at a party in Islington. She left the planet with Zaphod Beeblebrox six months prior to its destruction and now serves as a crew member aboard the Heart of Gold.

A robot equipped with "Genuine People Personalities" technology who is perpetually depressed and bored because his vast intellect is rarely utilized. He serves aboard the Heart of Gold, offering cynical commentary and complaining about the pain in the diodes down his left side.