Lady Gaga recently shared the movie's final trailer, and she sounds absolutely incredible singing "That's Life" in it. What we know about Joker: Folie à Deux is limited, but that'll change when it hits theaters in October.

Folie à Deux' co-star Joaquin Phoenix said she lost "a lot" of weight for it. Here's what to know about her diet and fitness routines.

Joker and Harley Quinn are sharing their madness with Gotham City as mayhem reigns in the trial of Arthur Fleck.

Folie à Deux does have quite a few scenes featuring music, Lady Gaga, who plays Harley Quinn, doesn't think of it as a musical at all.

EW's exclusive clip from the "Joker" sequel shows Gaga and Phoenix passionately kissing before passing a puff of cigarette between their lips.

Joaquin Phoenix had one note for Lady Gaga while shooting "Joker: Folie à Deux": sing worse. This isn't "A Star Is Born."

In a new featurette for Joker: Folie à Deux, director Todd Philips and stars Lady Gaga and Joaquin Phoneix discuss Gaga's role in the film. "She easily slipped into that world. It's not like she's trying to be Harley Quinn from the comic books. She's Lee in this world," Phillips shared.

Five years after “Joker” won the top prize at the Venice Film Festival, director Todd Phillips can’t help but be a little nervous about returning with its sequel

That certainly looks to be the idea in the latest trailer for Todd Phillips all-singing, all-dancing movie with music Joker: Folie À Deux, which sees Joaquin Phoenix's Arthur Fleck taking to the stand as he goes on trial for the televised killing of Murray Franklin (Robert De Niro) in Joker.

Lady Gaga is already making naysayers eat their words with just the teaser of Harley Quinn in Joker: Folie à Deux.