William Bowery explains himself.

When Taylor Swift dropped her surprise Grammy-winning, best-selling album Folklore in July 2020, fans initially had one major question: Just who the heck is William Bowery?

The mystery man was credited on two standout tracks — "Exile" and "Betty" — but he tellingly had no prior internet history or musical credentials, leading people to assume it was an alias. This led to rampant speculation that he could be Swift's boyfriend, Joe Alwyn; her brother, Austin Swift; or perhaps another singer-songwriter in the industry. Swift and her co-producers remained mum on his true identity for months, but at long last confirmed it was Alwyn in Swift's concert film, Folklore: The Long Pond Studio Sessions.

Now, Alwyn, who is making the promo rounds for his new Hulu and BBC Three show Conversations with Friends (out May 15), has opened up about being Bowery in a new interview with GQ U.K. In it, he explained that he was in a band during his school years called Anger Management, which fittingly performed covers of Marilyn Manson and Korn. And, during the pandemic lockdown, he would return to those roots a bit and mess around on the piano and work on composition. It was during these bouts of messing around that he created the melody and first verse of "Exile."

Taylor Swift and Joe Alwyn
Joe Alwyn opens up about working with Taylor Swift and why they kept it a secret
| Credit: Taylor Hill/FilmMagic; Mike Coppola/FilmMagic

"It was really the most accidental thing to happen in lockdown. It wasn't like, 'It's three o'clock, it's time to write a song!' It was just messing around on a piano and singing badly and being overheard and then thinking, you know, what if we tried to get to the end of it together?" he told the outlet. Alwyn also admits there's "probably a voice note somewhere that should be burned" of him singing the nascent versions of the song.

Alwyn says the process of working on the tracks with Swift, and watching them go on to actually be produced by the National's Aaron Dessner and featuring the vocals of Bon Iver's Justin Vernon, was "surreal." "Sending it to Justin with the idea of doing a duet and getting voice notes back of him singing over the top and stuff was surreal. It was a perk of lockdown," he says. (In addition to the Folklore tracks, Bowery is also credited on follow-up album Evermore's "Champagne Problems," "Coney Island" and "Evermore.")

Of his pseudonym, which is a portmanteau of his great-grandfather's name and a favorite New York locale of his, Alwyn says it was something he and Swift decided on in the hopes that people would focus just on the music. "The idea was that people would just listen to the music rather than focus on the fact that we wrote it together," he says.

The actor — who also has Claire Denis' The Stars At Noon premiering in competition at Cannes later this month — says he currently has no plans to do more music, but he's happy with what he and Swift created. Of the experience, he says, "It was fun to do it together, and I was proud of it. It was nice getting such a positive reception."

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