IT’S A SUNDAY AFTERNOON in Tribeca, and I’m in Taylor Swift’s loft, inside a former printing house that she has restored and fortified into a sanctuary of brick, velvet, and mahogany. The space is warm and cozy and vaguely literary—later, when we pass through her bedroom en route to her garden, 10 percent of my brain will believe her wardrobe might open up to Narnia. Barefoot in a wine-colored floral top and matching flowy pants, Swift is typing passwords into a laptop to show me the video for “You Need to Calm Down,” eight days before she unleashes it on the world.

I have a sliver of an idea what to expect. A few weeks earlier, I spent a day at the video shoot, in a dusty field-slash-junkyard north of Los Angeles. Swift had made it a sort of Big Gay Candy Mountain trailer park, a Technicolor happy place. The cast and crew wore heart-shaped sunglasses—living, breathing lovey-eyes emoji—and a mailbox warned, LOVE LETTERS ONLY.

Swift and a stream of costars filmed six scenes over about a dozen hours. The singer-songwriter Hayley Kiyoko, known to her fans as “Lesbian Jesus,” shot arrows at a bull’s-eye. The YouTube comedian-chef Hannah Hart danced alongside Dexter Mayfield, the plus-size male model and self-described “big boy in heels.” The Olympic figure skater Adam Rippon served up icy red snow cones. Swift and her close friend Todrick Hall, of Kinky Boots and RuPaul’s Drag Race, sipped tea with the cast of Queer Eye.

The mood was joyous and laid-back. But by the end of the day, I wasn’t sure what the vignettes would add up to. There were shoot days and cameos I wouldn’t observe. For security reasons, the song was never played aloud. (The cast wore ear buds.) Even the hero shot, in which Swift and Hall sauntered arm in arm through the dreamscape at golden hour, was filmed in near-total silence.

For weeks afterward, I tried to sleuth out a theory. I started casually. There was a “5” on the bull’s-eye, so I did a quick search to figure out what that number might mean. Immediately I was in over my head.