Steven Tyler surprised fans by showing up during the encore of a Cadillac Three show in Nashville over the weekend.

Tyler joined the trio for a rendition of the Aerosmith hit "Sweet Emotion."

"I want to introduce you to my friend, Mr. Steven Tyler," said Cadillac Three's Jaren Johnston.

Tyler walked on the stage wearing a Cadillac Three t-shirt on which he had crossed off the word three and written the word four.

"Having our fans and the place we grew up party, dance and get loud, man, was everything to us," Johnston said after the show. "And, seriously, to have one of our biggest idols, and now friend, sing with us, we definitely couldn't dreamed this up when we started this crazy journey."

Cadillac Three are currently prepping the release of their sophomore album.