Douglas Adams died in May 2001 at the age of 49. He was the author of five books in the Hitchhiker's Trilogy, including The Hitchhiker's Guide to the Galaxy; The Restaurant at the End of the Universe; Life, the Universe and Everything; So Long, and Thanks for All the Fish; and Mostly Harmless. His other works include Dirk Gently's Holistic Detective Agency; The Long Dark Tea-Time of the Soul; The Meaning of Liff and The Deeper Meaning of Liff (with John Lloyd); and Last Chance to See (with Mark Carwardine). His last book was the bestselling collection, The Salmon of Doubt, published posthumously in May 2002.