When US talk-show host Jimmy Fallon took over The Tonight Show in February, he brought his house band of five years with him. Their TV gig secure, veteran hip-hop crew the Roots grow steadily more challenging – and interesting – on record. Not everything here sounds like Dies Irae, a blast of radio interference, squelching and screaming at the album's midpoint, which references the end of days. But there is a distinctly apocalyptic feel to this mosaic of hard-knock tales from urban America – "No idea how much time's left, fuck trying to cherish it," a street-hardened voice spits, chillingly, on The Dark. Bracing, brilliant.