The DC Extended Universe has been, put gently, a gigantic mess over the past decade. Most of DC's poster boy heroes lack what it takes to stand out as the face of the franchise, and the one that does have what it takes came from the unlikeliest of places.

If Hollywood rumor is to be believed, Henry Cavil won't be returning to Superman, ditto Ben Affleck and Batman. Wonder Woman is still around but was apparently only good for one film before the disastrous sequel. The Flash, Black Adam, Blue Beetle, all these heroes are still awaiting their day in the sun, leaving only one character and one performance left to be the flagship of the DCEU.

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Harley Quinn was one of many game-changing additions to the DC Comics canon created for Batman: The Animated Series. Originally designed to be a comedic henchwoman for big villain The Joker, Harley has taken on a shocking level of popularity and importance. Dr. Harleen Quinzel didn't make it into the proper DC Comics canon until 1999, but it's hard to imagine the franchise without her today. One of the most dynamic and complex characters in the Batman mythos, Harley has been the hero, villain, anti-hero, and everything in-between. Harley is all over the comics today, and she's also made a massive mark on DC's video games, cartoons, and TV series. That's part of what made it so surprising that Harley Quinn didn't hit the big screen until 2016.

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David Ayer's Suicide Squad did a lot of things very wrong, but in that tragic film, the crew made exactly one perfect decision; casting Margot Robbie as Harley Quinn. The first big-screen portrayal of Harley Quinn is, bar none, the best thing the DCEU has introduced to pop culture. Even through 2016's Suicide Squad's murky nightmare vision, Margot Robbie brought perfect enthusiasm, physicality, and depth to the long-awaited character. Fans got to see a fast-tracked version of Dr. Quinzel's love affair with Jared Leto's terrible Joker, and her part still holds up without issue. She's like a diamond in the rough, the only thing worth remembering about a movie that might as well have been written out of the canon. Luckily, the studio saw what audiences saw in her and gave Robbie's Harley Quinn a chance to shine.

Birds of Prey: And The Fantabulous Emancipation of One Harley Quinn holds a number of records in the DCEU canon. Longest title for one. It's the shortest film in the franchise thus far, coming in at just 109 minutes. It's also, tragically, the least financially successful film in the DCEU. Among all this, it also earns the title of the most heavily underrated film in the franchise. It's hilarious, fast-paced, action-packed, beautifully realized, and a perfect distillation of the character in a way no other DC film has managed. If someone had never heard of DC Comics and watched every character's big solo debut, from Man of Steel to Shazam, to Birds of Prey, they'd come away with the strongest understanding of Harley Quinn. That film perfectly tied her in with a brand-new team, then sent her off on her own, but the amazing thing is, when she was dragged back to her old digs, she was perfect yet again.

Harley Quinn is thrust back onto the big screen in James Gunn's valiant attempt to revive the failed franchise with The Suicide Squad. After her grand introduction alongside nearly a dozen characters who get instantly slaughtered, Harley Quinn spends a solid chunk of the runtime as a captive. The Suicide Squad is an ensemble piece, which typically implies it would have less time to focus on its individual characters. That's why it's so shocking that James Gunn gave Harley Quinn a perfect end to her character arc early in the film.

Quinn finds herself captured by an ambitious national leader who desires her hand in marriage. He seems great and Quinn is instantly enthralled, but once he reveals his darker intentions, she makes a choice. Quinn's speech about the trauma she's experienced and the violent walls she's had to put up to stop herself from getting hurt again is an emotionally throttling moment. It's over so quickly, but its impact can be felt throughout the film. Top that off with a pulse-pounding action scene, Quinn's tearful joy as her friends come to her rescue, and the touching final scene, and they've got a main character.

Rick Flag, Peacemaker, Harley Quinn, Thinker and Bloodsport walking in the rain

Studio failures and the limitations of franchise storytelling have prevented most of the big DC names from having a solid, multi-film arc. Harley Quinn may be the only character to have the kind of full story that fans love from these cinematic universes. Margot Robbie's Harley Quinn has the performance, narrative weight, and flawless execution that should make her the flagship character of the DCEU. Put her in everything. Build the franchise around her like the MCU did Iron Man. Or, at least learn from the one unambiguous success to grant every character the power of Harley Quinn.

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