When fans first met Harley Quinn in the DC Extended Universe, she was already imprisoned by Amanda Waller for the Task Force X project. For that reason, there wasn't much of her time as the Joker's right-hand woman shown, save for a few flashback segments. And yet, this window of time in the past is home to perhaps one of the most important moments in the DCEU: the death of Robin.

After her debut in 2016's Suicide Quad, Harley Quinn recently appeared in Birds of Prey (and the Fantabulous Emancipation of One Harley Quinn). Next, she's already set to appear in James Gunn's sequel/reboot, The Suicide Squad. What's more, Warner Bros. is reportedly developing a new Harley Quinn film. And while this next film could be any number of possibilities, from a solo venture to another team-up film, it is the perfect opportunity to finally give a definite answer to the big Robin mystery.

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Robin Suit BvS

In Batman v. Superman: Dawn of Justice, fans first learned that Bruce Wayne had lost his crime-fighting partner to the Joker. Then, in Suicide Squad, it was revealed that Harley Quinn was complicit in the murder of the Boy Wonder. But that's all fans know of Robin's death. When it comes to the Batman mythos and the DCEU as a whole, this sticks up as perhaps the biggest unanswered question: which Robin died, and how did it happen exactly?

Well, Harley Quinn's next big-screen adventure (post-The Suicide Squad) would be the perfect time to tell that story. After all, after the events of Birds of Prey, Harley has officially made the turn from villain to anti-hero. Now doing her own part in taking on the bad guys, Harley could use that time to earn a bit of redemption after one of the worst things she did: help the Joker kill one of Gotham City's greatest heroes.

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This quest to atone for her past misdeeds could open the door for a flashback sequence that would finally show what happened to Robin, and what part Harley played in it. Moreover, if Jared Leto and Ben Affleck would be up for it, there could be even room for a cameo from Joker and Batman. If not, then the focus could be squarely on Robin and Harley. Either way, it's this connection between the two of them that could fuel Harley's story going forward.

Better yet, in the presence of the DCEU, this story could set up the debut of the next Robin, or perhaps even Batgirl. Fans don't yet know if Harley will return in a Birds of Prey sequel, or in something else altogether. If the case is the latter, then Harley could run across new members of the Bat-family for a reluctant team-up. This would certainly prove to be an interesting adventure, and it could be the catalyst for the film delivering the answers fans have been waiting on for more than four years (and counting).

Currently, there is a renewed interest in Zack Snyder's take on the DCEU. In fact, the release of Zack Snyder's Justice League on HBO Max will once again cast a spotlight on the movies that helped lead up to the ensemble film, including Batman v. Superman. With the focus back on this era of the DCEU, now would be the time to strike while the iron is hot. Snyder's Dawn of Justice introduced that mystery, which means Harley Quinn's next cinematic adventure could finally close that loop.

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