Margot Robbie Margot Robbie will play Harley Quinn, the Joker's girlfriend and sidekick, in the upcoming "Suicide Squad" movie. Photo: Reuters

It looks like Warner Bros. is going full steam ahead with the casting of the upcoming film “Suicide Squad.” According to recent reports, the studio is closing in on casting Margot Robbie to play the fan-favorite role of Harley Quinn.

Collider reported the “Wolf of Wall Street” actress is close to signing on to play the demented girlfriend/sidekick of The Joker. For those unfamiliar with the character, USA Today reported she first appeared in "Batman: The Animated Series" as Dr. Harleen Quinzel. While interning as a psychiatrist at Arkham Asylum, she managed to arrange a psychoanalysis with The Joker, Gotham’s most twisted mind. During their session, The Joker manipulated the young woman into falling in love with him. She helped him escape and later, after being injected by Poison Ivy with something to give her super strength and super speed, engages in an “abusive on-again, off-again relationship with The Joker.”

If the rumors about “Suicide Squad” casting are true, Robbie will co-star alongside Oscar winner Jared Leto, whom The Hollywood Reporter said is the front-runner to take on the role of The Joker. According to the outlet, the “Suicide Squad” in the comic books is made up of a team of convicted super villains tasked to do missions for the government. In exchange, they receive reduced prison sentences.

According to CNN, Leto and Robbie are among names like Tom Hardy and Will Smith who are reportedly in discussions with Warner Bros. about taking on the roles of bad guys in the film, scheduled for release Aug. 5, 2016. Smith and Robbie have a professional history together as she will co-star with him in 2015’s “Focus.” Fittingly, she’ll be play the role of a sort of sidekick/protégé to Smith’s villainous con-man character.

IGN noted Jesse Eisenberg may reprise his role in “Dawn of Justice” as Lex Luthor and return for “Suicide Squad.” It’s worth mentioning no casting news has been announced officially for the movie, but DC is likely looking to bring on some great actors to helm its expanded film universe if it hopes to keep up with the folks over at rival Marvel Studios. Robbie and Leto would be a good start for the studio.