Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch is a comedic fantasy novel written as a collaboration between Terry Pratchett and Neil Gaiman. The two authors were living in England at the time and had known each other for years. According to them, the collaboration began when Gaiman sent half a short story to Pratchett.
While Pratchett wrote most parts involving the characters of Adam Young and the Them, Gaiman wrote most parts involving the Four Horsepersons of the Apocalypse. Pratchett claims the character of Agnes Nutter entirely as his own. The rest of the novel was written by “whoever”--either of the authors or sometimes both of them. They estimated that overall, Pratchett wrote more “raw words” of the novel than Gaiman did and was in charge of editing the text overall, in part due to Gaiman being busy working on his graphic novel series The Sandman.
While Good Omens was first published in 1990, it has enjoyed continuous popularity and has been hailed numerous times as a cult classic. There have been numerous rumors about its adaptation into a movie or television series. but plans for such an adaptation have never surpassed the earliest stages. In 2014, the novel received a radio show adaptation on BBC Radio 4.