Warner Bros and DC Entertainment are reportedly developing a movie focusing on Harley Quinn and The Joker, the antagonists from the 2016 film Suicide Squad. Sources say that both Margot Robbie and Jared Leto are set to reprise their roles as Quinn and The Joker, respectively, in the movie titled Harley Quinn vs The Joker. 

Sources also add that this yet-to-be-confirmed project seems to be in addition to Suicide Squad 2, which will likely be directed by Jaume Collet-Serra, and the in-development Gotham City Sirens, which is confirmed to see the return of Robbie as the pig-tailed super-villain with David Ayer on board to direct. 

The new project is described as a Suicide Squad spin-off and DC Entertainment President and CCO Geoff is set to produce.