Love or hate Baz Lurhmann’s The Great Gatsby, one of the most hypnotic scenes of the film is the first. There’s no Leonardo DiCaprio or Carey Mulligan, simply the camera zooming in on the metallic, Art Nouveau Gatsby crest as The xx’s “Together” pings with melancholy coolness.

“I have yet to see it,” The xx’s singer-bassist Oliver Sim tells EW with a laugh. The track, which perfectly captures the fashionable aloofness and pending tragedy of Fitzgerald’s novel, was not written for the film specifically. “We wrote it for Coexist. It didn’t fit on the album,” Sim says. “Then Baz Lurhmann approached us and asked if we wanted to write for it and we tried, but then we remembered this song and we went back to it and it fit perfectly with the brief he gave us: melancholic yearning, and the scene that he had told us to visualize with Gatsby and Daisy lying in bed staring at the green light.”

The xx’s sound is a lot like that green light: gently pulsing, ephemeral and distant. And whereas Daisy Buchanan tells Gatsby with envy and admiration, “You always look so cool,” I would say of The xx: They always sound so cool, in every sense of the word. On 2012’s Coexist, echoing guitar and keyboards fold into restrained vocals that tell stories that ache with a self-possessed longing.

“There’s no moral of the album or anything,” Sim says. “The first album came from a very different place then the second. We started writing those songs when we were so young, 15, 16. When you’re writing songs at that age, for me, it wasn’t really coming from a place of experience. So there was a lot of sharing my expectations and observations of other peoples’ relationships … Then Coexist was a bit more — it came from a place of experience. It was a bit of venting and it was therapeutic to make.”

Whether writing from observation or experience, the English indie rockers have hit a global nerve: Coexist received top praises from Rolling Stone, Pitchfork and Spin. “We try to be universal,” Sim notes. “I don’t mean to exclude people in our songwriting, which is why we use a lot of ‘you’s’ as opposed to ‘he’s’ or ‘she’s.’”

In the future, he says that The xx would like to explore poppier dance music, and Sim would like to write music for other artists. When asked if he could write a song for anyone, who it would be, Sim didn’t skip a beat. “You know, might as well aim for the stars. I’m a huge Beyoncé fan … That would be a dream.” The xx and Beyoncé? That’s a dream EW can get behind.

The xx plays 8 pm Tuesday, May 28, at McDonald Theatre; $35.