Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch (1990) is a fantasy novel written in collaboration between Neil Gaiman and Terry Pratchett. Due to the different status of the authors in America and Great Britain, American editions credit Gaiman before Pratchett, while British editions credit Pratchett before Gaiman.
The book is a comedy, concerning the birth of the son of Satan, the coming of the End Times and the attempts of the angel Aziraphale and the demon Crowley to avert them, having become accustomed to their comfortable postings in the human world. A subplot features the gathering of the four horsemen of the Apocalypse - War, Famine, Pollution, and Death - the last of whom is characterised in a manner reminiscent of the personification of Death in Pratchett's Discworld novels.
A film is in the works and has been for some time now, under the direction of Terry Gilliam. It is currently indefinitely stalled through lack of sufficient financing. The tedious history of this project and similar experiences with projected films of various of Gaiman's other works (including The Sandman series) have led to his cynical view of the Hollywood process, a view which occasionally surfaces in his weblog and in some of his short fiction.