Thematically and structurally, "Black America Again" distills the essence of its parent release like few other pre-album singles. Filled with love, grief, and rage, Common traces institutionalized racism back to Christopher Columbus and covers many of the after effects, from slavery to police shootings, from housing projects to gentrification. Karriem Riggins, the veteran multi-instrumentalist and producer who contributed to Common's 1997-2007 run, potently layers live instrumentation -- Robert Glasper's leading piano, Esperanza Spalding's melodic bass, J-Rocc's percussive scratches -- with an array of samples that includes a propelling breakbeat and an empowering James Brown monologue. Real-life Stevie Wonder arrives toward the end with a proud affirmation of his own. The product of a fully unified super session, this album was produced entirely by Riggins, assisted by Glasper on two other cuts. Common operates at full power. He rarely sounds as if he's merely filling space with his words, rhyming with purpose about spiritual and physical sustenance, reflecting upon his upbringing, lamenting recent tragedies, and fantasizing about a peaceful future in which the world is run by women. He often targets mass incarceration, delivering one of his most moving narratives in "A Bigger Picture Called Free." It's easy to overlook the rapper's remarkable rhythmic aptitude in understated lines like "My pops -- y'all built and destroyed him with prescriptions of poverty, dope, and unemployment." Some love songs, highlighted by the sweetly bobbing "Love Star," wouldn't lose much with Common removed from them, but they -- along with spiritualized opener "Joy and Peace" -- effectively break from all the grim matter. The basic track list provides no indication that this is the most collaborative Common album since Electric Circus. Most of the vocalists formally linked to the track titles -- Bilal, Tasha Cobbs, Syd, BJ the Chicago Kid, and PJ among them -- are utilized more like an ensemble throughout. Glasper and J-Rocc are among the frequently heard instrumentalists, while keyboardist James Poyser, bassist Robert Hurst, and trumpeters Theo Croker and Roy Hargrove make appearances. And then there's Riggins on drums, bass, and the application of a Dilla-like sample scope -- obscure library recordings, Gentle Giant, Ol' Dirty Bastard, the works. All that's here, dark or bright, is vital.