BLAKE SHELTON performed TWO free surprise concerts at a couple of clubs late last week.  It started on Thursday afternoon when he Tweeted, "Greenville, South Carolina . . . You!  Blind Horse Saloon tonight!  Be there."

Blake wasn't kidding . . . and by Thursday night, people were lined up outside the club waiting to see the show.  Here's a YouTube video of the fans waiting.  I love the "Ain't nobody got time" guy who comes in at the 0:39 mark.

Season premiere of the voice tonight from 8pm to 10pm on NBC-TV - featuring Usher, Blake, Shakria, and Adam.