Make no mistake, DC Comics fans: the shared movie universe launching with Batman V Superman: Dawn of Justice won't be a place for only the most reliable comic characters. After DC's 'Big Three' grace the screen, it's director David Ayer's Suicide Squad which will carry the baton forward, introducing villains that could exist in the DCMU for years to come.

Now that the stars of the film have been revealed, fans of both well-known and more underrated villains look to be pleased. We've made the case that such a varied ensemble adventure is just what DC's movie universe needs, but some members of the cast seem more likely to stick around than others.

We've already given a crash course in Jai Courtey's Boomerang and Will Smith's Deadshot, but next up is a beloved Bat-villain with a history and mystery that even fans may not be aware of: the 'Joker's Girlfriend,' Harley Quinn.

5. The Origin

Artwork courtesy of Inanimate Objects

Unlike most of the villains in Batman's Rogues Gallery, Harley Quinn was created specifically for Batman: The Animated Series as a right-hand woman for the Joker. Sporting the black and red outfit of a harlequin jester - and a thick Brooklyn accent - Harley was an immediate hit with fans, as was her cartoonish personality, unflappable sense of humor, and devoted affection to her beloved "Mistah J."

But the character's future was cemented when creators Paul Dini and Bruce Timm offered a glimpse into Harley's history in the 1994 comic titled "Mad Love": Harley was more than just a fan or recruit of Joker's, having overseen his treatment at Arkham Asylum as Dr. Harleen Quinzel, M.D. (proof that no one with even a slight taste for insanity could resist Joker's manic charms).

Dr. Quinzel's professional curiosity turned to infatuation and obsession, and through Joker's manipulation she offered him freedom - and a sidekick - throughout the animated DC universe.

4. The Update

Harley Quinn Actress Suicide Squad Movie

The most significant (or at least longest-lasting) change to Harley didn't come in the comics, but as part of Rocksteady Studios' Batman: Arkham Asylum video game. Casting off the bodysuit and jester's cap, the grittier, more adult-oriented Harley was given a boost to both sex appeal and violent tendencies, again acting as the humorous hammer to Joker's crazed mastermind.

Both Arkham Asylum and its sequel Arkham City proved that fans of the animated series still held a special place for the Joker's girlfriend, and DC Comics took notice. When the company's 'New 52' reboot brought the entire comic universe back to square one, Harley wasn't just made a star of the new "Suicide Squad" comic series, but given a standalone title all her own - and with it, a brand new origin.

No longer fooled by the Joker's lies (that he, too, came from a broken home), Dr. Quinzel is only swayed when Joker smuggles in a special gift: a severed thumb. Specifically, the thumb of the wealthy drunk driver who killed her father (without any punishment). With the thumb came Joker's promise to show Harley how to wield the same power.

After murdering a professional rival, Joker takes Dr. Quinzel to Ace Chemical (where he was doused in chemicals that resulted in his own 'rebirth') and puts his new love through the same process. Harley Quinn emerges, every bit as transformed as her dear "puddin."

Surprisingly, the two eventually parted ways; Harley apparently able to survive the separation, and in some ways, treat it as an opportunity. The previous incarnation of Harley was a literal punching bag for Joker, being treated as a nuisance, with signs of genuine affection few and far between. The new Harley showed she was no lovesick puppy, pursuing a sexual relationship with Deadshot - another brash, homicidal leader - upon first joining Amanda Waller's 'Suicide Squad.'

In the years since, the Harley/Joker dynamic has been modified to more closely resemble an unhealthy dependency, with Harley able to lose herself in her own heightened reality, but the maniacal devotion to the Joker simmering below the surface.

With updated canon came brand new alternate visions of Harley; one of the best coming in the form of "Injustice: Gods Among Us", a limited series based on the video game of the same name. Writer Tom Taylor's parallel universe has become one of DC's best-selling titles, and has given Harley fans some of her best moments in recent years (we would go so far as saying that a live-action version of the character would be wise to take its lead from her "Injustice" incarnation).

In "Injustice", Harley is introduced as a woman whose distance from an abusive relationship has granted some... perspective. Even in the canon series, Harley is portrayed in a lighter tone and madness, never as homicidal or deranged as the Joker. That means that a film version in which she is more than just an amusing lunatic sidekick is still keeping to the established fiction.

Could these be clues as to the direction taken with Margot Robbie's Harley in live-action, or is the classic version (seen in Batman: Assault on Arkham) a more likely plan? Only time will tell. But as straightforward as the Joker may have become over the years, Harley remains (potentially) a much more complicated figure.

NEXT PAGE: The Powers, The Actress & The Future...

3. The Powers

The effectiveness of Harley Quinn in combat is hard to state: Dr. Quinzel may have been a gifted gymnast, but oversized wooden mallets haven't been used on the battlefield in some time. The most recent incarnation of the Suicide Squad swapped out such a mallet for a good old-fashioned sledgehammer (which Harley used to great effect), but despite the team's stated purpose - to carry out black ops likely to get the team killed - it's unlikely that Harley's fighting skills will be her defining quality.

Whether or not the rumored story details for the Suicide Squad movie are accurate, it's Harley's tenuous link to normal human behavior that will most likely be highlighted once joining the DC and Warner Bros. movie universe. That isn't to say she'll be bouncing off the walls like her animated self, but if she truly is unpredictable to the point of harming herself and others, then it's easy to see why Amanda Waller may wish to turn her loose on unsuspecting enemies.

Whatever the justification or weapons Harley is given to make herself useful on the Squad, it's the perspective offered by her mental state - never valuing life, death, or personal injury - that holds the most promise. Besides making her a handful in a fight, that freedom from worry has potential for some much-needed comedic relief.

Where the "Harley Quinn" comic series has embraced insanity and self-aware humor to the point of making the heroine 'DC's Deadpool,' not every incarnation is so over-the-top. Humor was just one way that Harley become a runaway star of the "Injustice" series; poking fun at the no-nonsense characters and elements of the DC universe as a surrogate voice for the audience without addressing them directly. For instance, pointing out the key flaw in Green Arrow's base of operations, the "Arrow Cave":

The many writers and artists handling Harley's newest adventures have resulted in a wide range of sanity levels and personalities attributed to her, so David Ayer has plenty of wiggle room to craft his very own spin. It's easy to describe Harley as simply 'a female Joker,' but if the studio plans to use the two as a package deal down the road, establishing some differences would be wise.

Knowing David Ayer's past work with ground-level crime drama (Training Day, End of Watch, Harsh Times, Fury), a certified Saturday Morning cartoon-level jester on the Squad isn't likely. But one half of a deadly couple who's willing to kill dozens - then drop a witty punchline - may come in handy.

2. The Actress

Suicide Squad Movie Harley Actress Robbie

More than any other member of the film's core cast, Margot Robbie (The Wolf of Wall Street) is the biggest question mark. The role of Harley Quinn has never been entrusted to a single person on such a high-profile stage, and Robbie's slim feature-film experience is hard to overlook. But even if Robbie stepped into the spotlight opposite Leonardo Di Caprio, her follow-up roles opposite Will Smith (Focus), and the indie hit Z For Zachariah (placing her alongside Chris Pine and Chiwetel Ejiofor) show her star is most definitely on the rise.

Robbie has recently stated that playing a character so unique and beloved is admittedly "intimidating," but reminds fans that the film - and her role - is still in its early stages (her next film is the political comedy The Taliban Shuffle).

What we do know is that Robbie has shown the ability to not just hold her own with some of Hollywood's biggest stars, but steal the spotlight from them with frequency. That will be well-served opposite Smith, Viola Davis, Jared Leto, and apparently even more seasoned actors - even if Harley Quinn is an overpowering personality herself.

Suffice to say that plenty of Suicide Squad enthusiasts will be lining up to see what chemistry Robbie has formed with Focus co-star Will Smith, the actor set to play the team's de facto leader Deadshot.

1. What Comes Next?

Given the bond between Harley and the Joker, her role going forward seems obvious; if the plan is to introduce Jared Leto's Joker to appear in a later Batman film, then Harley would presumably follow suit. That being said, Neither Leto nor the Joker are expected to need backup. If the solo Batman movie continues to draw from Frank Miller's "Dark Knight Returns" (a comic not including Harley), she could be given a fate all her own.

With Warner Bros. and DC Comics using Harley Quinn as the face of the Suicide Squad in the series' comic reboot AND the animated Assault on Arkham, it seems a big screen future with the Squad would be likely. The swirling rumors of a sprawling, interconnected movie universe may imply that keeping Harley confined to Suicide Squad and its potential sequel would be a missed opportunity. But if Smith's Deadshot and Robbie's Harley prove a potent mix onscreen, then bringing in new villains to back them up is an easy plan to follow.

And whether in an ensemble film or a solo story, there's plenty of new ground to break with the Joker's girlfriend - including some story angles largely ignored by most writers.

To anyone not up to date on Harley's comic appearances, her character may be largely seen as "thinly-developed" at best. But over the years, she's joined forces with Poison Ivy (who granted her immunity to poison and toxins), Catwoman, and even the Secret Six. (We previously explained why the most well-known "Secret Six" story arc could be adapted into a Deadshot-led Suicide Squad sequel, and Harley would fit the offbeat dynamics perfectly.)

Of course, there is the previously mentioned "Injustice" series, and its alternate timelines in which Harley revealed that she and and the Joker have a daughter named Lucy - a child that Harley has entrusted with her sister, since 'Mistah J' isn't one for familial attachments. If movie audiences are truly hungry for a new spin on the Joker, then dropping that bombshell would send plenty of shockwaves (and open up as many potential story lines).

Whether the plan for her character is based on compelling drama or franchise staying power, the bottom line is the same: if the plan is to view the Joker through a lens darkened by Frank Miller's "Dark Knight" vision, then Harley deserves just as much of an overhaul.

Conclusion

Those are the essential facts for any casual comic book movie fan to get a sense of what to expect from Margot Robbie's 'Harley Quinn 'in Suicide Squad - and realize that her one-note - and beloved - portrayals in the past may have overlooked some of her most intriguing aspects. Have we convinced you that Harley is more than a source of humor, or do you still have your doubts about the character or actress? Share your thoughts in the comments.

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