A softer Black Power Mixtape, Thunder Soul honors the stage band of Houston’s predominantly African-American Kashmere High School, whose funky arrangements led to multiple awards in the 1970s. Director Mark Landsman intercuts scenes of vintage Kashmere—mile-high Afros and “the Super Fly look”— with reminiscing band members, who, 30-plus years after last picking up their instruments, are preparing for a reunion concert. They also hope to honor the man who led them, Conrad “Prof” Johnson, increasingly frail but still dapper and self-possessed at age 92. Footage of the band at its height reveals an exceptionally tight, precisely choreographed troupe, easily crushing the mostly white, vanilla-sounding ensembles they compete against. Landsman’s documentary doesn’t dwell long on broader historical details (Jesse Jackson chanting “I am—somebody” essentially stands in for the black politics of the decade) or on controversy (a new principal’s lack of support for the band in the late ’70s isn’t really explained). This kind of reportage would interfere with the director’s goal: maximum uplift, which he largely achieves. Sometimes you just can’t fight the funk; as much as you might resist the film’s more maudlin scenes, not succumbing to the band’s signature tune, “Head Wiggle,” is impossible.