Margot Robbie Reacts to Leslie Grace's Casting as Batgirl (Exclusive)

On leaving The Joker behind in 'The Suicide Squad' and when she'll play Harley Quinn next.

Harley Quinn is back behind bars. When we first met Margot Robbie's Clown princess alter ego five years ago, she was locked up at Belle Reve in Suicide Squad, before being liberated (and fabulously emancipated) in 2020's Birds of Prey. But Harley is in the clink once again in The Suicide Squad, which is... Loosely related but not that loosely related, and connected but not that connected, to those other two movies. We'll let Robbie explain.

"It's not a sequel, prequel or a reboot, really, because some characters cross over that people met in Suicide Squad, the one directed by David Ayer, and then there's a whole ensemble of new characters," she told ET's Ash Crossan. "It's its own thing. It's kind of like the comic books. Depending on who the author is, the comic might be different, the tone might be different, it's like that."

In James Gunn's The Suicide Squad, Harley has been reenlisted by Task Force X leader Amanda Waller (Viola Davis) for a super-secret, super-suicidal mission to the South American country of Corto Maltese to stop a giant, mind-controlling starfish alien. All they have to do is not get their heads exploded first.

"I think the main difference is the rating," she added. "This is an R-rated film, and the humor is really pushing the boundaries, the violence is-- Like, there's sharks ripping people in half. But it's the kind of violence that's very, like, sensationalized and fantastical and so it fits with the world and it's still fun."

Warner Bros.

The Suicide Squad sees Harley alongside fellow returnees Colonel Rick Flag (Joel Kinnaman) and Captain Boomerang (Jai Courtney), as well as so-bad-they're-good recruits like Bloodsport (Idris Elba), Polka-Dot Man (David Dastmalchian), King Shark (Sylvester Stallone) and Weasel (Sean Gunn). One bad guy who's not in the picture this time? The Joker.

"She's definitely independent from Mister J for the first time," Robbie said. "Even though in Birds of Prey, they'd broken up at the start, she was still very much not OK with not being with him. In this one, she's not even thinking about him, which is really fun and just a new, interesting mindset and place for Harley to be in in her life. She's looking for new love, and she's looking in all the wrong places."

So, where might Harley pop up next? There's been no official word from Warner Bros., although the studio did recently cast In the Heights breakout Leslie Grace as Barbara Gordon, aka Batgirl, a character closely tied to the Birds of Prey in the comics. At the time of ET's interview, Robbie hadn't heard the news. (Or was very good at feigning surprise.)

"I didn't know that! Oh, how cool! That's wicked. She's amazing," she said, before joking of the two appearing onscreen together: "Yeah, I'm calling-- Warner Bros, can you put me through to DC? Yeah, thank you. I'm on it. Don't worry."

And Robbie is indeed ready to don Harley's signature pigtails again sooner rather than later, despite recent headlines that she needed a break from playing the character. "No, I've had enough of a break. I'm ready to do her again," she said. "I did Birds of Prey and The Suicide Squad back-to-back, so that was a lot of Harley all in a one year period, but that was a while ago now. I'm always ready for more Harley!"

The Suicide Squad is in theaters and streaming on HBO Max on Aug. 6.