Stone, 25, was conducting an interview for 2DayFM when the hosts surprised her with a blast from her past: a video message from the Spice Girls' Mel B.
"Oh my God, is Mel B talking to me? I'm going to cry. I'm so excited, I am legitimately crying," she said as she watched the clip. "I am the biggest Spice Girls fan ever."
Hosts Merrick Watts and Sophie Monk originally intended to have Mel B visit the show so she could meet Stone, but because Scary Spice couldn't make it, they decided to have her leave a message for the movie star.
"Hi Emma this is Mel B," the former Spice Girl says in the clip before thanking her for being a such a good fan and calling her out for liking Baby Spice the best.
You can check out a clip of the moment below.