Sundance Head reached back — way back — for his cover song on NBC's The Voice on Monday night (Dec. 12). The soulful country singer covered Etta James' "At Last" in front of a small orchestra and millions watching at home.

The Texan is one of three finalists with country roots, although former child star Billy Gilman is now pursuing a career in pop music. Head is a favorite, with a powerful voice and backstory that's leaving fans wanting more after every performance. His cover of "At Last" was slow, patient and not quite as soaring as his original song "Darlin' Don't Go."

A small group of doo-wop singers backed him, joining a string section and more traditional country instruments like steel guitar for a rich and complex arrangement. At the bridge, as a bead of sweat leaked from the brim of his gray cowboy hat, he did indeed hit those notes he's called a signature during Season 11. Coach Miley Cyrus stood looking dumbfounded by what she was witnessing.

"It's like somebody reached back in time," Head's coach Blake Shelton said afterward. "It's absolutely unbelievable."

For his duet with his coach Head chose a song by his father Roy Head called "Treat Her Right." While not a song that's popular to contemporary audiences, the funky country-pop-rocker touched on his backstory. "Treat Her Right" was a Top 5 hit in 1965. He'd go on to put three songs on inside the Top 40 chart, and add another three to Billboard's Country Top 40.

The winner of Season 11 of The Voice will be announced on Tuesday night (Dec. 13). Josh Gallagher, Billy Gilman and We McDonald are the other finalists.

Watch Sundance Head Sing "Treat Her Right" 

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