In a video posted to social media by HAIM -- made up of sisters Este, Danielle and Alana Haim -- the siblings and Stone stand in the middle of a residential street and begin singing "Stop" by the Spice Girls.
In Stone and HAIM's recreation, the girls begin belting out the song's chorus while perfectly mimicking the original dance from the video. Throughout breaks in the song, each of the women reveal that they're teaming up to send a lucky fan to a Spice Girls concert in London, England. The winner will even get to hang out with Stone, HAIM and the Spice Girls themselves backstage at the show.
The funds raised from the Omaze contest will support charities including Girl Up, Child Mind Institute, Los Angeles LGBT Center and more.
"I saw them in concert in the ‘90s. I saw them at O2 Arena in 2008, and they recently announced a new tour and I will be going to that somehow," she said on The Tonight Show Starring Jimmy Fallonback in November. "I don’t think tickets are on sale yet, but I’m gonna figure it out.”
While on the show, Stone also revealed that she began requesting to be called Emma -- instead of her given name, Emily -- in honor of Emma Bunton, a.k.a. Baby Spice, and the group as a whole.
"I was super blonde, and my real name is Emily, but I wanted to be called Emma because of Baby Spice and guess what, now I am,” Stone shared. "So, that’s pretty messed up.”
"It wasn’t necessarily because of her, but yes, in second grade, did I go up to the teacher and ask her to call me Emma, yes I did. And was it because of Emma Lee Bunton from the Spice Girls? Yes it was,” she admitted.
Just days later, Stone gushed to ET's Nischelle Turner over her excitement at the girl group getting back together.
"It's very real. I'm very excited," she said. Though Stone admitted that she's "bummed" Beckham won't be making an appearance at the shows, she added, "I want to let her be free, do whatever she wants to do."
Watch the video below for more on Stone's Spice Girls love: