It's an ordinary Thursday lunchtime for Arthur Dent until his house gets demolished. The Earth follows shortly afterwards to make way for a new hyperspace express route, and his best friend has just announced that he's an alien. At this moment, they're hurtling through space with nothing but their towels and an innocuous-looking book inscribed, in large friendly letters, with the words: DON'T PANIC. The weekend has only just begun . . .