Despite being intended as a miniseries based on a single book, the first season of Good Omens was so successful that Azieraphale and Crowley are returning for a brand-new story beyond Terry Pratchett and Neil Gaiman's novel in Good Omen's season 2. Initially, Martin Sheen's Azieraphale and David Tennant's Crowley were only expected to feature in a single series, as the source material only covers one story. The show's popularity earned it a second season, which surviving co-writer and showrunner Gaiman has crafted from scratch. Because there was only one book written, the second season is surrounded by mystery, and this has led to Good Omens season 2 updates and news being highly sought after.

https://screenrant.com/good-omens-season-2-release-date-cast-plot-updates/