Paris Hilton and Kim Kardashian West are working on a secret project. Their secret project is not, in fact, all that secret. On Thursday evening, the socialite/Simple Life star/aspiring DJ posted a brief, extremely filtered clip to her main Instagram feed, in which she and Kardashian West tease their mystery undertaking: “Can you guess what we’re doing today?” Kardashian West asks, vamping for the camera. “It’s a surprise,” Hilton adds, in similar constant motion, as though they’re sharks and if they stop moving they’ll suffocate. They wear coordinating silver dresses, garments Hilton made so iconic on her 21st and then 36th birthday that Kardashian West’s younger sister Kendall Jenner emulated the look more than a decade on.

The surprise isn’t all that surprising if you read the caption and take a look at the link in Hilton’s bio. “I can’t stop looking at my #BestFriendsAss,” she wrote in the caption, accompanied by a music note, peach, and eyes emoji. In her bio, she links to the Spotify page for a forthcoming single entitled, you got it, “B.F.A. (Best Friend’s Ass).” From that, we can glean that they’re almost certainly working on a music video. So it was that on Thursday in Los Angeles, TMZ reported, the two were hanging out near the Nightingale Plaza club in Hollywood, accompanied by the Britney Spears impersonator Derrick Barry (in full “I’m a Slave 4 U” regalia), drag queens, shirtless men, and snakes. Kardashian West is nothing if not committed to snakes.

Kardashian West and Hilton have been friends since they were “little girls,” as Hilton described in a 2015 interview with E! News. “We’ve always been friends.” It’s been five years since Kardashian West’s ass first broke the Internet, and now it’s getting a music video. This might be the first time that Kardashian West’s derrière specifically became the subject of a music video, but it’s certainly not her first video appearance. There was Fergie’s kind of ingenious “M.I.L.F.$,” the video for Kanye West’s “Bound 2,” and, of course, Fall Out Boy’s “Thnks fr th Mmrs,” in which Kardashian West plays Pete Wentz’s love interest and hooks up with a monkey.