That's the music video for Lorde's contribution to the Hunger Games: Mockingjay Part 1 soundtrack, "Yellow Flicker Beat." She also curated the album, and recruited The Lumineers, Ariana Grande, Major Lazer, Charli XCX, CHVRCHES and Miguel to contribute songs.
Lorde just turned 18, and celebrated by enjoying a tall glass of orange juice with Taylor Swift or one of her clones.
Swift has a little fun with the rumors that Lorde is actually significantly older than 18 (or a middle-aged male geologist). Swift writes on Instagram: "It's Ella's 18th birthday technically but we all know she's really 300 and knows all the secrets of the universe. #ELLAflickerbeat"
She does seem to know something the rest of us don't — I'll give her that.