OutKast [ tickets ]'s follow-up to the bazillion-selling "Speakerboxxx/The Love Below" is "Idlewild," the soundtrack to the Atlanta's duo's new film set in the Depression-era South. While not as tight or hook-heavy as their 2003 breakthrough, this disc nevertheless offers jams galore that bridge the group's appreciation for jazz and swing with modern R&B and hip-hop.

All through this 25-track disc--no less than six cuts are skits--Andre 3000 and Big Boi infuse their alien brand of hip-hop with the flavor of the swing era, from spare, yet lively arrangements ("When I Look In Your Eyes"), to the album's production--including scatological piano, lead vocals that sound as if they were recorded on the Apollo stage, and songs punctuated by a chorus of singers lurking in the background.

On "Mighty O," the pair lifts Cab Calloway's "Minnie the Moocher." "Idllewild Blues (Don'tchu Worry 'Bout Me)" is built on a looping, bluesy, acoustic riff. The ultimate realization of this nostalgia is "Call the Law," a fine, pulsating, piano-driven, gospel-inspired throwdown sung by Jonelle Monae, herself a throwback to the singers of the speakeasy joints of Kansas City or New Orleans.

Andre and Big Boi deliver accessible, if weird, music. On "Idlewild" their influences do reach back to the '20s and '30s, but OutKast's modern funk and R&B touchpoints can be heard as well, especially on the wimpy "N2U," a decidedly Prince-inspired tune, and the better "Idlewild Blues," which recalls Stevie Wonder's "Superstition."

No question, several cuts here sound like quintessential OutKast. Hyper rap tracks like "Morris Brown," "Chronomentrophobia" or "Peaches" would sound natural on any of the group's discs.

Maybe the most revealing thing about "Idlewild" is that OutKast's sound--as modern and progressive as it is--has always shown traces of all strains of African-American music, from Cab to Stevie. "Idlewild," while certainly not flawless, makes that fact more undeniable than ever.