With its 'Mississipi Burning' style motifs, relentless barrage of channeled frustration and intellectual thuggery, 'Rising Down' is the latest lyrical tour de force to come out of the original hip-hop band's troubled conscience.

Abrasive and belligerent but never without a sense of purpose, the Philadelphia sextet's eighth studio album is a slow burning politically-charged epithet that sees the introduction of a new addition to their extensive arsenal: the Fender Rhodes organ. The sonorous tones dominate the dark soundscape.

At the point of the spear is the title track, a Dickensian netherworld of global warming death knells and labour exploitation. Guest artist Mos Def puts in one of his finest verses — "Identities in crisis and conflict diamonds, blindin' staring at lights till they cryin', bone gristle popping from continuous grindin', grapes of wrath in a shapely glass" — and Styles P provides the perfect counterfoil.

MC Black Thought lets rip like a sawed-off shotgun on '75 Bars (Black's Reconstruction)', a claustrophobic first-take over a muffled synth-and-drumbeat, and sounds like he could go on for 75 more. The Fela Kuti afrobeat tribute of 'I Will Not Apologise' and the harrowing tale of drug addiction and reclusion that is 'I Can't Help It' further the downbeat dimension, and in 'Lost Desire' Talib Kweli's hard-hitting and eloquent street commentary immediately finds the mark. The intricate 'Singer Man' throws up three different perspectives of violence before the record's triumphant exclamation mark, the uplifting 'Rise Up'.

Then, like an ingrown toenail, comes the bonus track Birthday Girl. This inexplicably weak moment is an eerie ode to an 18-year-old groupie's coming of age, featuring Fall Out Boy's Patrick Stump on the chorus, and does not belong on this album. Or any other, for that matter.

That said, this 'bonus', the, at times, unimaginative production and unrelentingly oppressive lyricism are battle scars, not fatal wounds. This is the finest Roots vehicle to date, the culmination of over a decade of anticipation and unfulfilled potential.