Pharrell Williams and Chad Hugo, a.k.a. the Neptunes, are nothing if not ambitious. Their production techniques rule pop radio, but they hunger for success that obliterates genre lines. Hence, N.E.R.D., in which Williams, Hugo, and cohort Shae attempt to reach the rock audience without alienating the R&B and hip-hop camps. Fly or Die doesn't quite turn this trick, but at least the group goes about its business in a singularly twisted way.
Among the guest stars on Die are Lenny Kravitz, who pokes his usual retro shtick into "Maybe," and Good Charlotte's Joel and Benji Madden, recruited to croon on the jaunty adolescent curio "Jump." In the end, though, star power is less important than coherence -- a quality most of the tracks lack. Fortunately, these guys are talented enough to make self-indulgence intermittently entertaining. "She Wants to Move," the first single, is a perky mess that employs both hand claps and dog barks. Strap in -- it's gonna be a bumpy flight.