Danny Boyle and Alex Garland have done it again. In the early 2000s, 28 Days Later became the most popular and influential zombie movie in decades, with its fast-moving, virally infected, not-quite-undead marauders rampaging through a post-apocalyptic England. Now Boyle and Garland have reunited with 28 Years Later, easily the most talked-about horror movie since Sinners, and the biggest zombie movie since the PG-13 dilutions of World War Z back in 2013. Compared with the countless familiar zombie movies and TV shows that have popped up since the original movie, 28 Years Later is a thorny, challenging, unpredictable work, which means there’s plenty to discuss now that it’s spent a well-attended weekend in wide release. Here are some major spoiler-heavy topics related to the film’s style, themes, sociological implications and, of course, that ending.