Music

The pop diva and the sisters of HAIM serve as backing dancers and vocalists while Nelly performs his 2002 mega hit at the St. Louis, Missouri show on Tuesday, September 29.

• Sep 30, 2015

AceShowbiz - Nelly is the latest guest on Taylor Swift's "1989" tour. The rapper made a surprise appearance during the pop diva's show in St. Louis, Missouri on Tuesday, September 29 for a live rendition of his 2002 mega hit "Hot in Herre".

Joining the two superstars for the performance were the girls of HAIM. Wearing all-white, the sisters busted out some choreographed moves and served as backing vocalists alongside Swift while Nelly performed his song.

HOT IN HERRE @derrtymo feat @haimtheband Yes we made up a dance yesterday in the dressing room.

A video posted by Taylor Swift (@taylorswift) on Sep 29, 2015 at 10:05pm PDT

"WHAT?!" "...OH." @derrtymo @haimtheband

A video posted by Taylor Swift (@taylorswift) on Sep 29, 2015 at 11:19pm PDT

Swift shared some videos of the performance with her Instagram followers. In a caption of one clip, she revealed she and the Haim sisters came up with the dance moves just "yesterday in the dressing room."

Old friends. @derrtymo has come out to surprise the crowd on my last 3 tours. I absolutely adore him.

A photo posted by Taylor Swift (@taylorswift) on Sep 29, 2015 at 11:12pm PDT

The HAIM members also tweeted their excitement after they got to dance with Nelly. "I just danced with @Nelly_Mo with @taylorswift13 OFFICIALLY LOST MY CHILL," Alana Haim wrote. Este Haim posted a photo of them on the stage and said, "Casually danced behind Nelly on my last night of tour."

casually danced behind Nelly on my last night of tour ��� pic.twitter.com/kvAlybTUxp

— ESTE FUCKING HAIM (@jizziemcguire) September 30, 2015