'Joker: Folie à Deux' Trailer: Lady Gaga's Harley Quinn Makes Her Debut Alongside Joaquin Phoenix's Joker

The star-studded, musical sequel premieres in theaters Oct. 4, exactly five years after the original movie debuted.

The world's a stage and it's time for Joker: Folie à Deux to step into the spotlight. On Tuesday, Warner Bros. Discovery released the first trailer for the Todd Phillips-directed, star-studded sequel to 2019's Joker.

While the exact details of the project have been previously kept under wraps, it's clear that the film is a continuation of the Joker origin story told in the first film. That movie followed Batman's nemesis, Arthur Fleck, as he turned from comedian to villain. 

Based on the DC Comics story about how the Joker and Harley Quinn came to fall in love, Folie à Deux features Joaquin Phoenix reprising his role as Joker alongside Lady Gaga, who joins the cast as Harley Quinn -- who is typically depicted as Joker's psychiatrist at Arkham Asylum turned lover. 

In the comics, Joker is a patient at Arkham Asylum after his arrest and is put under the care of Dr. Harleen Quinzel. Joker slowly turns Quinzel against her better judgment until he eventually pushes her into a vat of chemicals, bleaching her skin and driving her mad.

In Folie à Deux, Harley is a fellow Arkham Asylum patient who seemingly becomes a new muse to the imprisoned Joker.

"I'll tell you what's changed," Joker says in the trailer. "I'm not alone anymore -- that's what we should be talking about!"

The trailer ends with Harley at Arkham Asylum as she draws a happy face with red lipstick on the glass partition between her and Joker. "I want to see the real you," she tells him.

Zazie Beets also returns for the sequel as Sophie Dumond – a single mother who lives in the same building as Joker. Newcomers include Steve Coogan, The Banshees of Inisherin star Brendan Gleeson, and Catherine Keener, who all star in undisclosed roles.  

As confirmed in 2023, the trailer reveals that Folie à Deux is a musical that features surrealist fantasy elements and spins the Joker and Harley Quinn love story on its head while bringing the audience into the twisted mindscape of the titular ill-fated duo.

The musical film will reportedly include at least 15 cover songs, similar to Moulin Rouge starring Ewan McGregor and Nicole Kidman.

Last Tuesday, the film's cast and crew dropped the first poster for the upcoming sequel, teasing fans with their first official look at the main couple. The poster shows the pair dancing in the spotlight of a blue-hued room in their infamous clown makeup. Phoenix, 49, sports comic-accurate green hair while Gaga, 38, wears her Harley Quinn gold locks pulled back into a bun. 

"The world is a stage. Joker: Folie à Deux trailer coming April 9. 🃏," wrote the "Bad Romance" singer in her Instagram post on Tuesday. She was first announced to be joining the cast back in August 2022, months before they were first spotted filming in and around New York City. 

Warner Bros. Pictures

Margot Robbie and Kaley Cuoco have also played the role of Harley Quinn, with the latter currently providing her voice for the titular animated series on Max. Robbie portrayed the character in 2016's Suicide Squad, 2020's Birds of Prey, and 2021's The Suicide Squad. In an interview with ET back in 2022, the actress said she was thrilled to see Gaga step into the role. 

"I think she's going to do an amazing job. I'm so excited, it's all I could've ever hoped for Harley was that she would become one of those characters, kinda like Batman or Hamlet, that gets handed from actor to actor, everyone gets a go at playing them," Robbie said. "So, I think it's just credit to her as a character that people want to see her in multiple iterations. I'm excited."

Joker: Folie à Deux premieres in theaters Oct. 4, exactly five years after the original movie debuted.

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