It’s true that Zack Snyder’s extended cut of Justice League had a lot of action sequences that Joss Whedon got rid of in his middling theatrical version, but the whopping 4-hour director’s cut also includes a ton of scenes that address the bigger DCEU continuity and its numerous characters.
After all, if there’s anything that the filmmaker set out to do with his bespoke Snyder Cut, it was to lend more depth to the shallow superheroes we saw in the initial 2017 iteration. But despite the inclusion of many secondary players like Lex Luthor, Slade Wilson, Iris West and Mera, Margot Robbie’s Harley Quinn is nowhere to be found. A conspicuous absence, all in all, especially considering the fact that she got her own spinoff flick, though admittedly it was a box office flop, in 2020.
Luckily, Jared Leto’s Joker makes a significant and spectacular appearance at the end of Snyder’s Justice League which also reveals the fate of his former flame. In the exhilarating epilogue to the movie, Bruce experiences another Knightmare involving the future of the world and Darkseid’s conquest. In it, he and Mr. J have formed a reluctant alliance and are on the run from an evil Superman, whereupon they get the opportunity to have a proper heart-to-heart after years of fighting.
In spite of this grudging truce, though, the two are clearly antagonistic towards one another. When the Clown Prince of Crime brings up Robin’s death, Batman hits back by mentioning how Harley Quinn died in his arms and made him promise to kill the Joker slowly. “She begged me, with her last breath, that when I killed you — and make no mistake, I will f***ing kill you — I do it slow. And I’m gonna honor that promise,” the Dark Knight says with anger and hatred.
Of course, there’s a good chance that we’ll never see this particular scene unfold on screen within the DCEU, but at least Zack Snyder made the effort of determining the Maiden of Mischief’s fate in his Justice League.