Missy Elliott could be the premier singles artist of her generation. Since changing the sound of hip-hop with 1997's Supa Dupa Fly, she's released a string of brilliant records, but she shines brightest in the realm of the perfect pop single–and its offspring, the flashy music video. Sneak peaks at her latest evolution and reinvention, the first singles from albums by Elliott and her partner Timbaland have transcended the subcultures of hip-hop and R&B to become pop-culture events. "Pass That Dutch," from her new This Is Not A Test!, marks Elliott and Timbaland's latest gift to Top 40 radio; while it's characteristically infectious, it builds on the glitchy dance-floor minimalism of past triumphs, rather than striking out in bold new directions. "Wake Up" is far more audacious, pairing a socially conscious lyric to production that finds the middle ground between the anthemic pop-rap of Ludacris' "Stand Up" and El-P's dystopian minimalism. The familiar but irresistible feel of "Pass That Dutch" characterizes the album as a whole, which defies easy categorization by rifling through Elliott's past triumphs. Her latest isn't sonically revolutionary like Supa Dupa Fly, dark and spare like Da Real World, a salacious club record like Miss E. …So Addictive, or an old-school manifesto like Under Construction, though it contains elements of each. As usual, Elliott's R&B songs sound soggy and antiquated compared to the brash, spiky newness of her uptempo hip-hop, but This Is Not A Test! breezes by too briskly to get bogged down by its weaker moments. Equal parts 'round-the-way girl, futuristic dance diva, sonically progressive critical darling, and super-freak, Elliott has earned the right to tread a little water artistically, especially when the results are this fun. While critics and audiences have embraced the winning team of Timbaland and Elliott, they've never really warmed up to the team of Timbaland and Magoo. That's unlikely to change with Under Construction Part II, whose title underlines just how frustrated Timbaland is with being revered as a producer but dismissed as a rapper, a theme explored at length on "Don't Make Me Take It There." Under Construction Part II lives up to its title with its terrific first single, "Cop That Shit," which finds Timbaland flipping an old-school flow alongside Magoo and Elliott over snake-charmer production. Timbaland has always been a master of minimalism, but after "Cop That Shit," the disc's production sometimes gets a little too spare, particularly during its weaker first half. Magoo simply doesn't have Elliott's charisma or personality, and while Timbaland has an intriguing sonic presence, Under Construction Part II lacks the inspired guest performances and strong melodies that made the duo's last album, Indecent Proposal, such an overlooked treasure. (It doesn't help that the second single, "Indian Flute," is little more than a dim echo of Indecent Proposal's near-perfect "Indian Carpet.") Together, Timbaland and Magoo remain an underrated, entertaining duo, but Under Construction Part II will likely do little to catapult them out of Missy Elliott's long shadow.