On her massive American stadium tour, Taylor Swift seems to be resurrecting the gimmick where she sings a song with a different guest at every show. Over the weekend, she brought the Weeknd to the stage in New York. And last night, when she was playing Washington, D.C.’s Nationals Park, she introduced her pop superfriend Lorde. The two of them sang “Royals” together, since stadiums are no place for guest-artist deep cuts. And while Swift is a perfectly composed stadium-pop machine at this point, Lorde still looks crazy excited that she gets to sing her song in front of all these thousands of kids. She’s still a performer, but she looks absolutely human in a really endearing way. Below, watch a fan-made video of the two singing together and check out a few Tweets from Lorde and Swift about the occasion.

just laughing like "this is our job how lucky are we/this stadium is so loud and pretty/we are best buds/KILLING IT" pic.twitter.com/wNXNkLapFV

— Lorde (@lordemusic) July 14, 2015

i'm gonna talk more about the show when i see it in full tomorrow.. be prepared for live tweeting and/or a long reference-heavy tumblr post

— Lorde (@lordemusic) July 14, 2015

but seriously, @taylorswift13 is the leader of a great and beautiful galaxy that i'd live in forever

— Lorde (@lordemusic) July 14, 2015

When your friend flies across the world to surprise your crowd with 'Royals' bc she's a wondrous angel. @lordemusic pic.twitter.com/zDdjtc7U3v

— Taylor Swift (@taylorswift13) July 14, 2015

Should we talk about what’s going on with Taylor’s shorts? Because I don’t understand what’s going on with Taylor’s shorts.