3. The Killing Joke
This is where we get into spoiler territory kids, so hold on to your petunias if you don't want to know what happens. Batman 24# is not just part of the Batman origin story, it's also the Joker origin story (well... kinda). In Alan Moore's The Killing Joke, debatably the most famous comic book of all time, we got a version of where the Joker came from for the very first time. Now of course it was coupled with many get-out clauses, as a Joker origin always is, but it is still widely accepted (more so after a version of it was used in Tim Burton's 1989 Batman movie) as the most credible theory out there. Snyder tells a vaguely similar tale, having Red Hood One (the leader of the Red Hood gang) fall into a large vat containing a cocktail of recently created chemicals. This happens in real time rather in flashback form, and there are an equally large number of reasons it might not be the creation of the Joker, given the guy who falls in is revealed not to be the leader of the gang anyway, but someone who murdered the real leader and took his place. We're not here to analyse whether the character is or is not the Joker though, as there's no answer to that question, so we'll simply note the allusion and move on. Something else taken from The Killing Joke, though much more subtle this time, is how the story is told entirely through dialogue. This lack of internal captions is a wonderful little homage to Moore's masterpiece and once again creates a feeling that, despite this being new continuity, every Batman story is still in some way connected.