CMA Music Festival attendees were already excited to hear the evening's scheduled performers at the Nissan Stadium Thursday night (June 9). So when Cam and Lady Antebellum showed up unannounced to sing “Burning House” and “Need You Now," well, that was just the cherry on top.

Cam had teased a big surprise on her socials, but kept her lips tightly sealed. The surprise was worth the wait. She, Hillary Scott and Charles Kelley traded off lines during "Burning House," and it's safe to say Cam could easily become a fourth Lady A member; their vocals melded together beautifully.

The "Mayday" hitmaker invited fans to sing along to last chorus. "You gotta do me one favor; you've gotta put your arms around each other like you love each other. C'mon y'all, we all need to get touched now and then. Show the love. I don't care if it's hot," she laughed.

At the end, Cam exclaimed, “I’m on stage with Lady Antebellum.” She also joined Lady A on their chart-topping hit “Need You Now," much to the delight of the 60,000 attendees.

The 2016 CMA Music Festival is in full swing, and it runs through Sunday (June 12). The annual event is the biggest country music party of the summer. For more information, visit the CMA Music Festival’s official website.

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