Of a piece with emerging Saint regular Future Islands, Small Black forges dark and murky Casiotone pop perfectly suited for the windowless, permanently predawn St. Mary Street interior. New Chain (Jagjaguwar), the Brooklyn band's October debut, deepens the squawking keyboards, foggy ether and sticky, static-y beats of its superb 2009 EP. Class Actress opens. Admission $5. 10 p.m. Thursday. The Saint, 961 St. Mary St., 523-005. www.thesaintneworleans.com.