Watch Busy Phillips Drink & Dye Michelle Williams' Hair Pink

What are best friends really for?

If you're asking Busy Philipps this question, one of your apparent responsibilities includes spontaneously drunk-dyeing your BFF's hair. After a "very Parisian" night at the Louis Vuitton runway show, the actress took to Instagram Stories to turn Michelle Williams' platinum-blonde pixie into a subtle pastel pink.

The hair color change alone is worth the watch, but it's all of Busy's some-15 slides, in its development and entirety, that will keep you laughing from dinner with baked potatoes and caviar—a.k.a. "the greatest thing that's ever happened to me," she said—through the dye process, to when the dynamic duo pass out for the night. Busy and Michelle take us on a journey, from when the pomp and circumstance of celebrity shed to when genuine girlfriends get raw and goofy.

"This is the moment—almost—where we turn into pumpkins, where all the beautiful clothes go back, and all the bags, and all the things," Busy explains, as they walk through their French accommodations. "Bye. Bye. Bye," Michelle responds.

After a video about Busy's impressive tequila-drinking skills—narrated by a friend named Stacy—we start to understand that there's no rest for the weary in this girl group: "Sleep on the plane tomorrow, that's the plan."

Then, from left field: "We're going to dye [Michelle's] hair pink—what do you think? Is this a good idea? Look at that hair—it's going to be pink," Busy says excitedly.

Pan to the bathroom: "Alright guys, here we are. We're going to dye Michelle Williams' hair pink," says the actress, laughing. "Michelle Williams—that's her name."

The two then debate on how long they should leave the dye, which looks like coral-pink slime, in Michelle's hair. Busy opens the negotiation with 20 minutes; Michelle counters with five seconds. They go back and forth until they settle on a time frame they are both comfortable with: "Honestly, after one minute we should stop," Michelle wins at last.

After the Manchester by the Sea actress initially dodges the application and runs away, we watch her slowly enjoy it while Busy gently massages the dye into her short locks.

"Michelle's hair is going to be perfectly millennial pink," says Busy, holding a glass of white wine.

"I want everything to be pink," says Michelle, also holding a glass of wine.

At this point, we naturally want to tap on to see the results, but their chemistry and friendship is so adorable that you'll probably want to hold on to every second of this hilarious exchange.

Finally, the reveal: "Guys, my best friend now has…I mean she's kind of naked and has slightly pink hair and it's fucking beautiful," says a gushing Busy. "She's like a little nymph."

Michelle's former platinum strands now have a tinge of pastel, perfectly complementing her bestie's more vibrant pink locks. Apparently, friends who dye their hair together, stay together. And there you have it: Celeb friendship at its best, displayed in one perfectly off-the-cuff, engaging Instagram Stories.

"I have more food to be eaten," finally says a sleepy Michelle at the end.

#Goals.