Warning: SPOILERS ahead for Birds of Prey.

Birds of Prey (And the Fantabulous Emancipation of Harley Quinn) sees the return of Margot Robbie's charmingly unhinged Suicide Squad character, and features several references to Harley's time as a member of Task Force X. Though it's predominantly a self-contained adventure, Birds of Prey does set the stage for Harley's next appearance in the DC Extended Universe: in James Gunn's sort-of-sequel The Suicide Squad.

Directed by David Ayer and released in 2016, Suicide Squad was highly anticipated after a series of awesome trailers, but the end result was disappointing (possible due to excessive studio interference). It was still a box office success, however, which was enough to earn it two follow-ups in Birds of Prey and The Suicide Squad. The latter film has been described as a "reinvention" rather than a straightforward sequel (hence the rather confusing title), but will feature a number of returning characters - including Harley, Jai Courtney's Captain Boomerang, Joel Kinnaman as Rick Flag, and Viola Davis as Amanda Waller.

Related: Birds of Prey Review: Harley Quinn's Wild Ride Is Fierce & Fun As Hell

The ending of Suicide Squad, in which Joker busts Harley out of prison, leads more or less directly into the start of Birds of Prey, where the couple have been through a rough break-up. Birds of Prey uses footage from Suicide Squad to explain Harley's backstory, but also helpfully recaps her whole life in animation, so you don't need to have seen Suicide Squad to get all caught up. Though Birds of Prey doesn't concern itself too much with setting up sequels, it does offer an update on another key Suicide Squad character - and sets Harley Quinn up as her own woman.

Captain Boomerang Seems To Have Escaped Belle Reve

Suicide Squad - Captain Boomerang character breakdown

When Harley raids a police station to find young pickpocket Cassandra Cain, there's a wanted poster for Captain Boomerang on the wall. Harley calls attention to it - pointing to the poster and saying, "I know that guy!" - and the poster is on screen for a considerable amount of time. The last time we saw Captain Boomerang he was confined to a miserable cell in Belle Reve, a prison for super-villains where the rest of the Suicide Squad were also being held captive. If the police are once again searching for him then that suggests he's out of prison, on the run, and robbing banks with his trusty boomerangs again.

It's possible that when Joker and his goons broke into Belle Reve to get Harley out, some of the other prisoners were also released - whether as a distraction, or just because Joker loves a bit of chaos. Then again, it's also possible that The Suicide Squad will begin with Captain Boomerang in the exact same place we last saw him, depending on how much Warner Bros. still cares about maintaining strict DCEU continuity at this point.

Harley Quinn Has Fond Memories Of The Suicide Squad

Harley Quinn in Suicide Squad

In the final act of Birds of Prey, the ladies are digging through Harley's treasure chest of costumes and weapons when Renee Montoya pulls out the "Daddy's Lil Monster" shirt that Harley wore in Suicide Squad. Harley quickly grabs the battle-scarred garment out of her hands and tells her that she can't wear it, because it has a lot of sentimental value. Though Harley was originally forced to join Task Force X against her will, she ultimately ended up bonding with her fellow team members - even calling them her "friends" by the end of Suicide Squad. It's also notable that her spell behind bars in Suicide Squad was the first time (that we know of) that Harley had been separated from the Joker since adopting her villainous alter ego. The movie even laid the groundwork for Birds of Prey's break-up by having the Joker abandon Harley to be caught by Batman.

Related: Why Birds of Prey Didn't Bring Back Jared Leto's Joker

The fact that Harley looks back on her time as part of Task Force X with fondness is significant, because unless she's thrown back into prison for The Suicide Squad, her involvement in the next mission may actually end up being voluntary. In fact, she could even be brought on board as an independent consultant.

Harley Quinn Is A Free Woman (With Her Own Business)

Birds of Prey

Harley starts out Birds of Prey as a harlequin without a master, lacking direction in life and under fire from everyone in Gotham City she's ever wronged (which is a lot of people). By the end of the movie she has her own business card declaring her to be "Harley Quinn & Associates: Badass Motherf***ers." Her only real associate is her apprentice, Cassandra Cain, but Harley is a pretty useful mercenary in her own right (even if she does have trouble spelling the word "mercenary").

This opens up a new way for Harley to join the team in The Suicide Squad: not as a prisoner, but as someone that Task Force X turns to for outside help. What Harley lacks in actual superpowers she makes up for with creative weapon usage and acrobatics. She also has strong links to Gotham's seedy underbelly, having spent many years as the Joker's right-hand woman. And, given her affection for her Suicide Squad outfit and her positive reaction to Captain Boomerang's poster,, it seems likely that she'd be willing to work with the team again - especially if Amanda Waller offers her some kind of immunity.

Based on what we know so far about The Suicide Squad, the name of the team is going to be more apt this time around. Gunn has teased that he won't be shy about killing characters off, and if Task Force X loses a lot of its new members then Waller may resort to recruiting one of the old ones. After all, there's a reason she considered Harley Quinn to be so valuable the first time around, and it was Harley who managed to get close enough to cut out Enchantress' heart in Suicide Squad's climactic battle.

It's currently unclear how large a role Harley Quinn will play in The Suicide Squad, which has a packed cast and lots of new characters to introduce. But if Task Force X is called upon to save the world again, then Amanda Waller definitely isn't above working with an escaped criminal to get the job done.

More: Every DC Movie Coming After Birds Of Prey

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