Given Costello’s longstanding affection for the music of New Orleans, it seems almost inevitable that he would eventually collaborate with Crescent City legend Alan Toussaint on a collection of swampland-tinged soul, Cajun music, and R&B. The fact that the partnership occurred in the aftermath of Hurricane Katrina lends a certain poignancy to the occasion, but certainly the atmosphere is not funereal. Opener “On Your Way Down” is all energetic funk, while the straight gospel of “The Sharpest Thorn” entrusts a higher power to sort out the bedlam. Here, Toussaint and company make quality bedfellows for Elvis’s Bayou ambitions.