Surely no composer can be said to have exploded on the 2019 film scene more than Hildur Guðnadóttir: Emmy-winner for the miniseries “Chernobyl,” Golden Globe winner for “Joker” and now Oscar-nominated for that film, all in less than four months.

The cellist-composer is a breakthrough artist in multiple ways: First, she is a female film composer whose work has garnered global attention; second, she is very much a citizen of the world, born in Iceland, based in Germany, working in both Europe and the U.S.; and third, her “Joker” music reminds filmmakers of the value of enlisting a composer early, even at the script stage, still a rarity.

Asked about her meteoric rise, she is quick to remind us that she’s “been doing film music for almost 20 years, so it’s been a long time coming.” She released her first solo album in 2006, scored her first feature (“The Bleeding House”) in 2011, began playing cello on fellow Icelandic composer Johann Johannsson’s scores in 2013 (“Prisoners,” “Sicario”) and was nominated as Discovery of the Year at the Ghent Film Festival in 2018.

Guðnadóttir is only the fifth woman to be Oscar-nominated for composing a dramatic score. Preceding her were American Ann Ronell in the 1940s, and Brits Rachel Portman, Anne Dudley and Mica Levi in the 1990s and 2000s.

“Traditionally you’d have a handful of white guys in Hollywood who would be doing these types of projects,” she says. “The industry is opening up to other sounds and,” she adds with a laugh, “other genders. There seems to be some inclusivity that is finally happening. I live in Berlin, I’m an Icelandic woman and I’m doing most of my work with people who are in L.A.”

She spent a day at the decommissioned nuclear power plant in Lithuania where “Chernobyl” was filmed, recording sounds that she then processed and turned into a score for the HBO limited series about the 1986 nuclear disaster in the Soviet Union. She was only the second woman in Primetime Emmy history to win an original-score award.

When director Todd Phillips called her about “Joker,” she was surprised. “Well, if you’re looking for someone to do an action movie, I’m not really sure I’m the right person,” she told him. He sent her the script and she loved it. “It was such an incredibly strong and powerful take on a character that I had grown up with and knew so well,” she tells Variety.

Improvising on her halldorophone, the electro-acoustic cello whose feedback qualities suggest “a Jimi Hendrix cello,” she attempted to “find my way into his head, and try to make music out of what I felt,” she says. “I found the notes, and I had such a strong physical reaction. It was like, ‘that’s him, that’s his voice.’”

This was months before shooting, Guðnadóttir recalls. Only later did she learn that Phillips had played this music on the set and that star Joaquin Phoenix began dancing to it — “his real-time reaction to the music,” Guðnadóttir says. “The music that we hear in the film is the original music that I wrote, and he’s dancing as he’s hearing it.”

Says Jeff Atmajian, who orchestrated and conducted the “Joker” score: “Hildur is a gifted composer-performer who is not only classically trained, but also highly skilled at the creation of original sound textures. She has an intuitive understanding of human emotions, and artistic integrity without arrogance. I think film scoring needs more of this.”