Sir Isaac Newton, renowned inventor of the milled-edge coin and the catflap!" "The what?" said Richard. "The catflap! A device of the utmost cunning, perspicuity and invention. It is a door within a door, you see, a ..." "Yes," said Richard, "there was also the small matter of gravity." "Gravity," said Dirk with a slightly dismissed shrug, "yes, there was that as well, I suppose. Though that, of course, was merely a discovery. It was there to be discovered." ... "You see?" he said dropping his cigarette butt, "They even keep it on at weekends. Someone was bound to notice sooner or later. But the catflap ... ah, there is a very different matter. Invention, pure creative invention. It is a door within a door, you see.

The next year the radio series became the basis for a BBC television mini-series broadcast in six parts. When he died in 2001 in California he had been trying again to get the movie project started with Disney which had bought the rights in 1998. The screenplay finally got a posthumous re-write by Karey Kirkpatrick and the resulting movie was released in 2005.

". Adams also wrote Dirk Gently's Holistic Detective Agency (1987) and The Long Dark Tea-Time of the Soul (1988) and co-wrote The Meaning of Liff (1983) Last Chance to See (1990) and three stories for the television series Doctor Who. He was a staunch atheist famously imagining a sentient puddle who wakes up one morning and thinks "This is an interesting world I find myself in—an interesting hole I find myself in—fits me rather neatly doesn't it? In fact it fits me staggeringly well must have been made to have me in it!" to demonstrate his view that the fine-tuned Universe argument for God was a fallacy.