Warning: potential SPOILERS for Birds of Prey

The first look at DC's Birds of Prey movie and its star, Harley Quinn has finally arrived, offering glimpses of all the DCEU's new Batman comic cast members. But Margot Robbie may have let a far bigger secret connecting Harley to Batman slip... one that suggests she's no longer the criminal fans met in Suicide Squad.

Rumors of a slightly different Harley Quinn coming to movie screens have circulated for some time, right down to her Suicide Squad tattoos being removed. But it's always been hard to tell which of those reports were wishful thinking from Suicide Squad's detractors, and which were conscious decisions behind the scenes of Birds of PreyThe newly released teaser footage shows Margot Robbie sporting all the same (visible) tattoos, but it's a photo of Harley Quinn's new wardrobe that seems to be the most potentially shocking clue.

That's all thanks to Harley's new necklace, trading a collar from her "Puddin" to a pendant bearing what may be a new kindred spirit: "Bruce."

Harley Quinn's "Bruce" Necklace

Harley Quinn Birds Prey Bruce Necklace

Interested fans looking to see the evidence for themselves shouldn't try to spot it in the teaser video, but instead look to the Harley Quinn selfie posted by Margot Robbie on her Instagram account. The confirmation that Birds of Prey was truly in production made headlines... but that also meant fans may have been too excited to take a closer look at Harley's necklace. We're referring to the silver one in the shape of a dog bone, completely in focus, and hard to miss once it's spotted. The necklace bearing the name "Bruce," which many will take as a clear nod to the Wayne billionaire who saved Harley's life before apprehending her (a flashback included in her Suicide Squad introduction).

RELATED: Birds of Prey Set Photos Reveal Harley's New Look

The questions raised are obvious ones: how could Harley Quinn know that Bruce Wayne is secretly Batman? Is this meant to suggest that Batman's secret identity may be known by other Gotham criminals? And just what does the necklace itself signify between Harley Quinn and the caped crusader - devotion, or a cruel joke? Before we dive into answering those questions, we should probably explain an alternate argument, which would mean this necklace isn't a reference to Bruce Wayne at all.

Bruce Wayne... or Bruce Timm?

There is a possibility that the necklace is intended as a nod to Bruce Timm, one of the co-creators of Harley Quinn for the acclaimed Batman: The Animated Series. While Timm and co-creator Paul Dini were referred to by the makers of Suicide Squad in conversation, such overt Easter Eggs to Timm and Dini weren't prominently featured in Harley's debut. That would certainly explain away the necklace, but it should be remembered that in taking such a photo, fans were expected to make a connection to Batman (DC's most famous Bruce). Not to me tuon that the main reason why pundits, comic fans, and bloggers would point to Timm is that it's a simpler explanation, not necessarily a better one. "Well.... she can't mean Bruce Wayne, right?"

But what if the most obvious answer really is the correct one? What if Harley Quinn now wears the name of her masked hero and fellow Gotham antihero around her neck? And if so, how much does it tell us about how Birds of Prey's Harley will have changed for the better? Trust us, not only would Harley knowing Bruce's secret be the more exciting answer... it would also bring Harley closer than ever to her current comic form, with her days as the Joker's plaything long behind her.

Page 2 of 2: How Batman Can Change Harley Quinn's Story

Margot Robbie Harley Quinn Suicide Squad

Could Harley Know Bruce Wayne is Batman?

The idea may be cast aside immediately by some, before even considering the ramifications it would have on the story (and whether it would make Harley better or worse as her own character). First of all, it's worth pointing out that in just about every version of a Batman universe, plenty of people know Bruce Wayne spends his nights as Batman. They keep the secret to themselves because they know what the audience does: outing him isn't their responsibility, and wouldn't make things any better... But it would bring the fury of Batman down upon themselves. That, and the fact that he is making the world a better place for all but the most despicable sections of the criminal world. So fans of Suicide Squad and DC Comics enthusiasts should ask: doesn't that explain why Harley wouldn't spill the beans, either?

RELATED: Margot Robbie Says Birds of Prey 'Isn't Very Serious'

As we mentioned before, it was Batman who saved Harley's life when Joker abandoned her at the bottom of Gotham Harbor. She was his enemy, but he kept to his code, valuing even her life (which so many others refused to). Since crossing lines to serve a personal sense of duty was her basic character arc in Suicide Squad, it makes the most sense to assume that if Harley were to uncover or deduce Bruce Wayne's alter-ego, she would keep it to herself. Of course, she would also make sure he knew that she knew his secret, with a wink and nudge sure to drive him batty.

Batman's Secret Proves Harley's a Hero

Harley Quinn in birds of prey holding a drink and wearing streamers on her arms

Some will view this shifting of Harley from a mayhem-loving villain who helped Joker kill Robin to a more virtuous character as "undoing" her Suicide Squad characterization, as opposed to continuing the trajectory the film was quietly charting. The film's trajectory takes her from an obsessive, infatuated lover of the Joker to an accepted, valued member of an admittedly unorthodox family. Ultimately, she even chooses to give up her personal desires out of a sense of duty and honor to her friends. While the ending may seem to undo that by having her return to Joker, David Ayer has revealed that his version of the movie ended with Harley Quinn leaving Joker for the Squad. Her debut film may have robbed her of the chance to change her own identity by "doing the right thing" - but Birds of Prey may give her that opportunity.

Little is known about the Birds of Prey story, beyond the characters and cast on hand. But with Ewan McGregor's Black Mask set as the villain, it's clear that Harley will be slotted into the "hero" role. And if she's going to be the same brand of hero as her current, Joker-free comic counterpart - the kind that actively saves Batman from being killed by Joker - her "Bruce" necklace is the simplest way to show audiences where her lines are drawn: this is a new, changed, morally sound Harley. Oh, and prove that she was smart enough to figure out Batman's identity where her former Puddin' never could.

The future of Ben Affleck's Batman is still a question mark, which means Harley may end up keeping a different Batman's secret - if and when they end up crossing paths again. Either way, that necklace sends Bruce a message, too: Harley is smarter and more capable than your common criminal. And more importantly, she may not be a superhero... but she's not someone Batman should see as a villain, either.

MORE: Suicide Squad Was a Massive Success (Despite Reviews)

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