When Lady Gaga makes her musical DC debut, fans are sure to know some of the words.

A source told Variety that the upcoming musical sequel Joker: Folie à Deux with Joaquin Phoenix will be ‘mostly a jukebox musical,’ consisting of at least 15 ‘very well-known’ songs.

One such number will be Judy Garland’s ‘That’s Entertainment’ from the 1953 musical The Band Wagon.

Although there’s a possibility for a couple of original songs to appear, it’s unknown who would write or perform those numbers.

Composer Hildur Guðnadóttir, who won her first Academy Award for composing the 2019 film, has been able to ‘infuse her distinctive, haunting [music] cues’ into each song.

Joker: Folie à Deux will be ‘mostly a jukebox musical,’ consisting of at least 15 ‘very well-known’ songs

Although there’s a possibility for a couple of original songs to appear, it’s unknown who would write or perform those numbers

Gaga joined the cast of the sequel as Harley Quinn in 2022, when director Todd Phillips announced it would be a musical.

Phoenix reprises his role as the eponymous comic book villain, following his Oscar-winning performance in the origin story.

Zazie Beetz also reprises her role, with Brendan Gleeson, Catherine Keener, Jacob Lofland and Harry Lawtey joining the cast.

Phillips penned the sequel with Scott Silver, reuniting after the original.

Filming began in December 2022 in New York and Los Angeles, wrapping in April 2023.

Joker grossed more than $1 billion globally, and the budget for the next installment has reportedly approached $200 million.

After the first movie showed the Arthur Fleck’s origins as the Joker and how his deteriorating mental health led to his life of crime and a stint at Arkham Asylum, the sequel will show his love story with Dr. Harleen Quinzel (AKA Harley Quinn).

Lady Gaga joined the cast of the sequel as Harley Quinn in 2022, when director Todd Phillips announced it would be a musical

Joaquin Phoenix reprises his role as the eponymous comic book villain, following his Oscar-winning performance in the origin story

Filming began in December 2022 in New York and Los Angeles, wrapping in April 2023

Gaga’s superhero movie debut comes after her Oscar-nominated performance in the 2018 A Star Is Born remake, which earned her Best Original Song for ‘Shallow.’

She has also served memorable performances in Machete Kills (2013), Sin City: A Dame to Kill For (2014) and House of Gucci (2021), as well as multiple seasons of American Horror Story.

Joker: Folie á Deux is set to premiere October 4 in theaters.