In House of Gucci, Gaga portrays Patrizia Reggiani, the ex-wife of murdered fashion dynasty heir Maurizio Gucci, played by Adam Driver.
Exploring the murderous fall of the Gucci dynasty, House of Gucci boasts a star studded cast and is set to hit cinemas later this month.
Co-stars Salma Hayek, Jared Leto and Jeremy Irons also walked the red carpet at the event in London’s Leicester Square.
But what is the true story between the film’s two central players, and how much does it stick to reality?
Here is everything you need to know about it.
What happened to Maurizio Gucci?
The crime drama follows Patrizia Reggiani, a socialite who had her fashion dynasty heir husband Maurizio Gucci murdered in a case that gripped Italy.
In 1972, Gucci married Patrizia; his father did not approve of their marriage, calling Patrizia "a social climber who has nothing in mind but money."
The couple had two daughters, Allegra and Alessandra, but in 1985, Maurizio told his wife he was going on a short business trip to Florence.
The following day, he sent a friend to tell his wife he would not be returning and that the marriage was over.
In 1990, Gucci began dating Paola Franchi, a childhood friend who had attended his first wedding. Gucci's divorce from Reggiani was finalised in 1994.
Maurizio, the head of the revered fashion house, was shot and killed by a hitman outside his office in 1995.
What happened to Patrizia Reggiani?
Reggiani, a high fashion personality, was convicted of orchestrating the murder in 1998.
According to prosecutors, Reggiani’s motives were a mixture of jealousy, money, and resentment towards her ex-husband.
They argued she wanted control over the Gucci estate and wanted to prevent her ex-husband from marrying his new partner, a marriage that would have cut her alimony in half.
In an attempt to get the verdict overturned, her two daughters argued a brain tumour had affected her behaviour.
Reggiani was jailed in 1998 - she served 18 years in prison and was released in October 2016.
Where is she now?
According to The Telegraph, since her release from prison, Patrizia lives in Milan, where she is frequently seen with her pet parrot on her shoulder.
What have the Reggiani and Gucci families said?
Speaking to the Associated Press, one of Maurizio Gucci’s second cousins said that the family was “truly disappointed”.
Patrizia Gucci said: “We are truly disappointed. I speak on behalf of the family. They are stealing the identity of a family to make profit, to increase the income of the Hollywood system.
“Our family has an identity, privacy. We can talk about everything, but there is a borderline that cannot be crossed.”
She also criticised the casting of Al Pacino as her grandfather, Aldo Gucci, saying: “My grandfather was a very handsome man, like all the Guccis, and very tall, blue eyes and very elegant.
“He is being played by Al Pacino, who is not very tall already, and [a photo from the House of Gucci set] shows him as fat, short, with sideburns, really ugly. Shameful, because he doesn’t resemble him at all.”
Speaking to the Italian magazine Novella 2000, Reggiani said in January earlier this year that she approved of the decision to cast Gaga as herself, stating that she likes her “immensely” and that “she’s a genius”.
However, Reggiani later said that she was “rather annoyed” that Gaga did not reach out to meet her in real life; according to sources from the Sunday Mirror, the decision not to meet with Reggiani was down to the producers.
They said: “The film has been Gaga’s passion project for a long time. She is determined to perfect the role and has been working all hours to get her portrayal of Patrizia right.
“Authorities at the time of the murder didn’t want journalists to interview her as they were afraid of giving her a platform. The same is said for now.”
When can I watch it?
House Of Gucci will arrive in UK cinemas on 26 November.
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