Lady Gaga plays Harley Quinn in Joker: Folie à Deux, the upcoming sequel to 2019's Joker.

But there's something different about Gaga's version of the iconic psychologist-turned-accomplice and girlfriend of the Clown Prince of Crime.

Who Is Harley Quinn?

Harley Quinn is one of the most recognizable characters in the entire Batman franchise. But while Batman made his brooding, caped debut all the way back in 1939, Harley didn't show up until more than 50 years later.

The character first appeared in Batman: The Animated Series in what was originally supposed to be a standalone episode in 1992.

READ MORE: ‘Joker: Folie a Deux’ Trailer: All the Easter Eggs You Missed

She made her debut as one of Joker's henchmen in Episode 22, "Joker's Favor," but the quirky, fan-favorite villain quickly became a recurring character, and eventually took on the role of Joker's obsessive, eventually scorned love interest. (Most recently, she's been depicted as an anti-hero or even hero, and the girlfriend of fellow supervillain Poison Ivy.)

How Did Harley Quinn Meet the Joker?

In the series, and as it's been canon within the Batman franchise since the early '90s, Harley Quinn was originally a psychologist at Gotham City's Arkham Asylum.

Harley real name Dr. Harleen Quinzel — met and fell in love with the Joker while treating him as her patient at the asylum.

Is Lady Gaga's Harley Quinn a Psychologist?

Much is still unknown about Joker: Folie à Deux and the specifics surrounding Lady Gaga's role in the film, other than that it's a musical and that Joker, played by Joaquin Phoenix, and Harley strike up a bad romance in the movie.

However, based on the first official trailer for the movie, it appears that Gaga's Harley Quinn will be a bit different from the previous adaptations of the character.

Specifically, it looks as though Gaga's Harley Quinn isn't Joker's psychologist in Folie à Deux, but rather a fellow Arkham Asylum inmate who becomes infatuated with Arthur Fleck, the man behind the clown.

Still, something tells us there's much more to be discovered about this version of Harley Quinn as Lady Gaga takes on the beloved character most recently portrayed in live action by Margot Robbie.

Watch the Trailer for Joker: Folie à Deux:

Joker: Folie à Deux is out Oct. 4.

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