Ever since Supa Dupa Fly first introduced the team of Missy "Misdemeanor" Elliott and Timbaland, the duo has had to deal with the towering expectations that accompany a string of groundbreaking singles. The two have continually risen to the occasion with mind-bending songs that stand up as both challenging sonic experiments and near-perfect pop singles. Their latest triumph is Under Construction's "Work It," an infectious exercise in dance-floor minimalism driven by a backward loop that symbolizes the album's winning collision of future funk and old-school vibes. Elliott begins her fourth album by vowing to return hip-hop to its essence, setting the stage for a disc saturated in nostalgia for the genre's golden age. Distraught over the death of close friend and collaborator Aaliyah, Elliott finds comfort in rap's colorful past on Under Construction, which looks back while surging forward. She and Timbaland load the album with sonic and lyrical references to days gone by, from Elliott's rethinking of Method Man's "Bring The Pain" (as a saucy ode to rude boys, roughnecks, and ragamuffins) to the Jay-Z-assisted reverie "Back In The Day." Timbaland pays homage here to Rick Rubin's groundbreaking work with Beastie Boys, which seems appropriate, since Rubin, Run DMC, and Afrika Bambaataa's influential early experiments with minimalist electro-funk still sound fresh and futuristic today. As usual, Elliott's forays into straight R&B, while respectable, pale in comparison to dance-rap tracks like "Work It," "Slide," and "Go To The Floor." Though she brackets the album with acknowledgments of Aaliyah's death, she isn't about to let grief get in the way of getting her freak on. A proud disco diva for a post-disco age, Elliott extols her brand of sexual politics throughout the disc, both in sex-saturated songs and (less effectively) in interludes that are less overwrought than Lauryn Hill's rants on Unplugged 2.0, but just as unnecessary. Still, it's the songs that matter on Under Construction. In the long shadow of death, Elliott and Timbaland's funky, feisty, infectious music joyously celebrates life.