Gary Oldman talks sobriety and 'Harry Potter' at Cannes

British actor Gary Oldman, who plays a washed-up alcoholic writer in new Cannes film Parthenope, said Wednesday he is celebrating 27 years sober.

The Oscar winner (Darkest Hour) also addressed controversial remarks he had recently made about his role in the Harry Potter films, which upset some fans of the boy wizard.

Oldman made the remarks at a press conference at the Cannes Film Festival after the premiere of Paolo Sorrentino's Parthenope.

The Italian coming-of-age drama, inspired by mythology, traces a beautiful young woman as she drifts through Naples and Capri.

Oldman appears briefly as famed novelist John Cheever, who in real life struggled with severe alcoholism -- a part that Oldman said was not much of a stretch.

"I just celebrated 27 years of sobriety," he said, to applause.

"I've been there," Oldman continued. "I know what that means. So coming to this role, there were things that I just instinctively understood.

"When Paolo said to me, 'I want you to play this sad, melancholic, drunken poet,' I went, 'Yeah, I kind of know what that is!'"

In the film, Cheever strikes up a bond with Parthenope, who adores the author's books but has grown disenchanted with her life.

Oldman was also asked about negative comments he recently made about his own performance as Sirius Black in film adaptations of J. K. Rowling's beloved Potter books.

Addressing why he had called the role "mediocre", Oldman clarified that he did not mean to "disparage anyone out there who are fans of Harry Potter and the films".

Instead, he regretted that he had not already learnt the character's tragic fate in later books when he first took on the role in 2004 movie Harry Potter and the Prisoner of Azkaban.

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