Warner Bros. Pictures and DC Entertainment are developing a live-action film pitting Harley Quinn against The Joker, Screen Rant has learned. This project is set within the DCEU and seems to be in addition to the Suicide Squad sequel (Jaume Collet-Serra is reportedly in the running to direct) and could be one and the same as the in-development Gotham City Sirens which sees Margot Robbie's Quinn in another feature directed by David Ayer - although we've not been able to confirm if Ayer's involved in this one yet so it could be an entirely separate project in addition to those two.

Both Harley Quinn (Margot Robbie) and The Joker (Jared Leto) were first introduced in 2016's Suicide Squad directed by Ayer, and both stars are attached to return for Harley Quinn vs The Joker. Note that this could just be the working title.

The project is described as a spinoff and Geoff Johns is set to produce. No story details or production dates have been set as of yet, but it's possible we learn more during the Warner Bros. panel at San Diego's Comic-Con International tomorrow where they kick off the big day in the convention center's Hall H.

Related: Warner Bros. Schedules Two DCEU Films For 2020

The logo treatment for the WB panel was designed in the style of Suicide Squad's colorful aesthetic so in addition to teasers and cast appearances for this fall's Justice League, and next year's Aquaman (currently in production), expect an updated slate of timelines and announcements.

At the moment, there's a lot of uncertainty about the direction and plans for the continuously evolving DCEU. With The Flash losing multiple directors, and Ben Affleck dropping out of the director's chair for The Batman - and new director Matt Reeves starting from scratch with the script - while announcements for Batman universe spinoffs are rampant, there's no clear idea yet of what the next few years look like in the DCEU. By comparison, the Marvel Cinematic Universe has dates and titles locked in for the next few years and has had that planned since a few years ago.

Related: Ben Affleck’s Future as Batman in the DCEU in Question

We do know director Patty Jenkins is returning for Wonder Woman 2, and we broke the big scoop last week that it'll see Chris Pine return alongside star Gal Gadot and be set in the '80s. It's reportedly set to be announced at SDCC alongside information on Suicide Squad 2. We don't yet know the plans for The Flash, Cyborg, or Green Lantern Corps in the new lineup of sequels and spinoffs which also includes Batgirl, Nightwing, and Gotham City Sirens in the Batman universe. Even that seems in question with today's report that Ben Affleck's future in the DCEU is in question, as was originally rumored when he dropped out of directing.

Jared Leto's Joker and Margot Robbie's Harley Quinn in Suicide Squad

There's also some confusion about where Shazam fits in, a film intended to pit the titular hero against Black Adam (to be played by Dwayne "The Rock" Johnson) but then reports hinted that Black Adam could get his own solo movie first. The most recent news on this front is that Shazam will enter production next year and, as DCEU boss Geoff Johns claims, The Rock won't even be in it.

Warner Bros. and DC Entertainment may take this opportunity to solidify a plan for the public, since every corner of the DCEU seems to be in a state of flux at the moment. Maybe that makes Harley Quinn vs The Joker a sensible addition to the slate, especially with Affleck on his way out. And maybe that's why Jared Leto won't confirm if he's in Suicide Squad 2. The Joker has this instead.

Update: Added clarification on other Gotham-based films potentially involving both The Joker and Harley Quinn.

Update 2: The Joker and Harley Quinn movie is confirmed, with Glenn Ficarra and John Requa (Crazy, Stupid, Love) to write and direct.

More: How Chris Pine Can Return in Wonder Woman 2

Stay tuned for more Harley Quinn vs The Joker and DCEU news here on Screen Rant!

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