About the book (from Wikipedia):
The Restaurant at the End of the Universe (1980) is the second book in the Hitchhiker’s Guide to the Galaxy comedy science fiction “trilogy” by Douglas Adams, and is a sequel. It was originally published by Pan Books as a paperback. The book was inspired by the song “Grand Hotel” by British rock band Procol Harum. It takes its name from Milliways, the Restaurant at the End of the Universe, one of the settings of the book.
The Restaurant at the End of the Universe begins just as The Hitchhiker’s Guide to the Galaxy ended. Arthur Dent, Ford Prefect, Trillian, and Zaphod Beeblebrox have just left the planet Magrathea when they are attacked by a Vogon ship. They find they are unable to use the Improbability drive to escape, as Arthur has accidentally jammed the computer with a simple request for a cup of tea which proved a rather difficult problem. Luckily, an ancestor of Zaphod’s, Zaphod Beeblebrox the Fourth, saves them.