After three decades of waiting, fans of Terry Pratchett and Neil Gaiman’s Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch recently—and finally—got to lay their eyes upon an adaptation of the classic work of comic fantasy. In 2019, all your favorite Good Omens characters—the angel Aziraphale (Michael Sheen), his demon BFF Crowley (David Tennant), pre-teen Antichrist Adam (Sam Taylor Buck), the Four Horsemen of the Apocalypse, and more came to life via an Amazon Prime and BBC Two co-production. On the 30th anniversary of the book's publication, here are some facts about the original, award-winning 1990 tome.

1. Good Omens has been adapted before.

The road to get Good Omens to the screen has been an arduous one (more on that later), but in 2015 a radio adaptation was broadcast on BBC 4. Among the cast were Mark Heap (Spaced), Peter Serafinowicz (Shaun of the Dead), Louise Brealey (Sherlock), and Colin Morgan (Merlin).

2. Terry Gilliam was working on a movie adaptation of Good Omens for ages.

The Oscar-nominated director of Brazil and Time Bandits was working on a Good Omens adaptation for years. Per an interview with Gaiman, it finally fell apart due to bad timing, i.e., Gilliam pitched Hollywood financiers shortly after 9/11.

"[Terry] said, 'Hilarious movie about the Antichrist and the end of the world,' and they said, 'Please go away, you're scaring us,'' Gaiman told The Empire Film Podcast in 2013.

3. Johnny Depp and Robin Williams almost starred in the Good Omens movie.

When Terry Gilliam was still onboard the Good Omens movie, he had his eye on Johnny Depp for the demon Crowley and Robin Williams for Aziraphale. In the new miniseries, they're played by David Tennant and Michael Sheen, respectively.

4. There was almost a film version of Good Omens that would have been very different from the book.

In 1992, two years after the book’s publication, Gaiman wrote a Good Omens script for Sovereign Pictures, who had requested he write something with some of the same characters but substantial plot differences. "Set in America, no Four Horsemen … oh god," was Pratchett's take on what the film would have been like. Fortunately for the writers, Sovereign went bankrupt and Gaiman and Pratchett got the film rights back.

5. Good Omens was nominated for a religious fiction award.

David Tennant and Michael Sheen in Good Omens (2019).Sophie Mutevelian/Amazon Studios

In Good Omens, Gaiman and Pratchett take a comic approach to religion that is, per Gaiman, "blasphemous against religious order, as blasphemous as you can get." Still, it ended up being embraced by some religious leaders. "When Terry and I wrote it we half-expected book burnings and bricks through our windows, and instead we were nominated for (but did not win) a religious fiction award," Gaiman wrote in 2013.

6. A sequel to Good Omens was in the works.

Certain elements from the Good Omens show are taken from a sequel that Gaiman and Pratchett talked about but never wrote. "There are a lot of characters whom I borrowed from the sequel, and had them do the things they would have done [in the sequel, but] earlier," Gaiman explained. "[The Archangel] Gabriel [played by Jon Hamm] is a prime example."

7. One interviewer didn't realize Good Omens was fiction.

For the first radio interview Gaiman and Pratchett did to promote the book, the radio host didn’t realize the book was fiction and instead assumed that the the pair had unearthed actual prophecies predicting the end of the world. "Once we realized, it was great fun," Pratchett recalled. “We could take over the interview, since we knew he didn’t know enough stop us."

8. Neil Gaiman WAS RELUCTANT to adapt Good Omens without Terry Pratchett.

Pratchett passed away 2015, leaving the future of any Good Omens adaptation—which Gaiman had previously said he didn’t want to do without Pratchett—up in the air. However, Pratchett wrote a letter shortly before he died giving Gaiman his blessing to continue without him. "I would very much like this to happen, and I know, Neil, that you’re very very busy, but no one else could ever do it with the passion that we share for the old girl," Pratchett wrote. "I wish I could be more involved and I will help in any way I can."

9. The American edition of Good Omens was originally longer.

The first American edition of Good Omens had about 700 more words than the British hardback. Pratchett explained that the book’s American publisher requested a passage on what happened to Warlock—the child who everyone thinks is the Anti-Christ, but who is actually a normal 11-year-old boy (there was a switch at the hospital).

“He was an American boy, you see, and she was certain that Americans would want to know what had happened to him. So we said OK, and wrote it. To the best of my recollection that was the biggest change, although there were other minor additions.” The Brits finally got that extra Good Omens sweetness once the UK paperback was set from the U.S. manuscript.

10. Floppy disks were an integral part of the Good Omens collaboration.

Pratchett and Gaiman collaborated on Good Omens by mailing floppy disks back and forth to one another. "This was back in 1988 when floppy disks really were pretty darn floppy," Gaiman wrote of the process. Initially, Pratchett focused on writing most of the stuff surrounding Adam and his friends while Gaiman focused on the Four Horsemen bits. By the time they were finished, they had both worked on everything and it was hard to know what belonged to who.