Jesse Elliott leads this alt-country/indie-rock band These United States. With roots in D.C. and Lexington, Ky, it's said to be one of rock’s best kept secrets, putting on a great live show. And for one night only, it’s free. Monday, Aug. 30, at 6 p.m. Kennedy Center Millennium Stage. Tickets are free. Call 202-467-4600 or visit kennedy-center.org.