Nearly half a century has passed since Os Mutantes released their self-titled debut, a foundational recording of Brazil’s psychedelic Tropicália movement. Sung predominantly in Portuguese, the album juxtaposes the dissonant with the beautiful, the messy with the mellifluous. Take “Baby,” which, with its entropic guitars, wobbly circus organ, and inaudible percussion, still feels like it could topple over at any second. Yet Arnaldo Baptista holds it together with his aching vocals. Forty-five years and nine studio albums later—that includes this year’s Fool Metal Jack—the band is still cranking out oddball, ecstatic sounds. (Sérgio Dias, the group’s sole original member, is now 63.) Whether the show is a career-spanning victory lap or something stranger, Os Mutantes remains a wily bunch. As the band’s debut reminds us, some of the best art comes apart in front of you. Os Mutantes performs with Capsula at 9 p.m. at Black Cat, 1811 14th St. NW. $20. (202) 667-4490.