The troubles of Richard Pryor’s life are well known — from his childhood in a brothel to his self-immolation via crack pipe — but arranged in a biography their impact is renewed. So grotesque was his upbringing that an early encounter with a dead baby in a shoebox warrants but a single sentence in David Henry’s and Joe Henry’s addictive, frenzied book (Furious Cool, Algonquin Books,£17.99,