What began as a formless side project seven years ago has become the unwitting spearhead of a significant movement. With Millions Now Living Will Never Die (Thrill Jockey), Chicago’s Tortoise has razed rock’s architecture and constructed something new from the rubble. Though the quintet still hasn’t finalized its blueprint, more and more the process of getting there has become its focus. The band’s eponymous debut shifted attention from song to sound. With the novel instrumentation of two bassists and three percussionists, Tortoise meted out long languid grooves rife with slowly developing melodies and gorgeous, sonorous textures. Then came Rhythms, Resolutions, and Clusters, a collection of jarring postmod remixes. With this album the band destroyed bland rock logic, looping linear structures back on themselves and reveling in the damage brought on by the knots. While the lush, cinematic new album isn’t quite the masterpiece the press claims it to be, it does find the band comfortably reaching new heights. The epic opener, “Djed,” however, is nothing short of brilliant. An ever-unfolding pastiche of grooves, sounds, and melody, the 20-minute piece proves that Tortoise can navigate in wide-open spaces, at least in the studio. Until this year the band couldn’t really pull it off live. But opening for the Dub Syndicate in February, it tightened its focus and made its explorations appealing to an audience larger than its usual apologists. Since then the band’s been touring nonstop, and reports from the road say it’s only getting better. The Sea and Cake and 5ive Style open. Wednesday, 9 PM, Metro, 3730 N. Clark; 549-0203. PETER MARGASAK

Art accompanying story in printed newspaper (not available in this archive): photo/Brad Miller.