Carrie Underwood and Brad Paisley soared to the top of their charts with their duet, 'Remind Me,' last year. The song, which Brad wrote, is part of his set list every night on the superstar's Virtual Reality tour. Staying true to form with the tour's moniker, Brad typically performs the tune during his show accompanied by a video of the blond beauty performing her part. But at a concert in Knoxville, Tenn. on Friday, March 2, Carrie decided to turn virtual reality into real reality!

"In a sneaky mood tonight...Stay tuned," Carrie tweeted early in the evening. Later, she posted, "Had so much fun tonight surprising @BradPaisley -- Thanks Knoxville!!"

Carrie waited until the song began before sneaking onto stage to begin singing her part live, which clearly thrilled her singing partner. "Coolest thing that's happened this tour!" he tweeted later that night, along with a photo of the two on stage.

Brad says he always knew he wanted to record a duet with his longtime CMA Awards show co-host. "I think [Carrie's] the best singer we have, maybe ever had," he told FOX News. "When she came into the studio and sang her parts for this song, she nailed it."

Carrie, who has enjoyed a close friendship with the West Virginia native over the years, recently joined the Twitter world and has already used the opportunity to rib her pal. "@BradPaisley thinks the world will end 'cause I'm tweeting," she posted shortly after joining. "I say we should get worried the day he STOPS tweeting! ;)"

Carrie's appearance on the Virtual Reality tour was just in time. Brad wrapped up the first leg, which included Scotty McCreery and the Band Perry, on Saturday, March 3, in Lexington, Ky. He'll continue with the second run in May. Keep track of his schedule here.

Watch Fan Footage of Brad & Carrie's Duet

Watch the 'Remind Me' Music Video

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