From Suicide Squad director David Ayer’s Twitter:

As most of us basement-dwelling nerds know (I live in Florida, so I am sans basement. This has always felt damaging to my nerd credibility), this teaser picture is a direct reference to the cover of Alan Moore and Brian Bolland’s The Killing Joke:

killing joke cover

From what the scuttlebutt says, this version of the Joker will be directly influenced by Frank Miller’s take on the Clown Prince of Crime in The Dark Knight Returns. Since that’s been the most obvious source of inspiration that we’ve seen for Zack Snyder’s Batman, it makes sense that Leto’s Joker would be similarly inspired. So while it’s a nice nod to fans to have this teaser picture tip its hat to Moore and Bolland’s seminal novel, I don’t see any reason to read into this picture as anything more than that.

I’m pretty burnt out on the Frank Miller version of these characters (The Dark Knight Returns is fantastic and important, but there are plenty of other great Batman stories out there from which to take inspiration) but since they haven’t been adapted to the screen yet, I’m still excited to see what will transpire. The cultural weight resting on Leto’s shoulders (thanks to Heath Ledger’s indelible performance in The Dark Knight) certainly adds another level of anticipation to this project. That and the fact that Suicide Squad seems to be a big defining picture in the grand scheme of the DC cinematic universe, and that is still weirding me out.