Dr. John goes on the attack in Locked Down, an utterly uncompromised 2012 collaboration with coruscating Black Keys guitarist Dan Auerbach. The 71-year-old hoodoo guru foments rebellion in "Revolution" and attests to his salvation in "God's Sure Good," riffing and jiving like his life depends on it. The music, a relentlessly rocking assemblage of R&B, funk, rock, and soul, sounds ageless and agile, like all of Louisiana distilled into a heady reborn brew.