Black Sabbath are one of the most outrageous yet longest-lived bands in the history of rock 'n' roll. This informative, idiosyncratic and beguiling book paints a vivid picture of their colourful early history - interwoven with all the most crucial news stories of the time: from Vietnam to Bloody Sunday and the space programme.

Where Rat Salad diverges from routes taken by most rock biographies, however, is in its detailed analysis of the band's first six albums. These chapters - think Ian MacDonald's Revolution in the Head meets Spinal Tap - occupy about half the book and persuasively explain the appeal of the music, its compositional artistry and its frequently audacious inventiveness.

Original and passionate, Rat Salad embraces a remarkably diverse cast of characters - from Ozzy Osbourne himself and the other members of the band through to Edith Sitwell, Breugel the Elder, John Milton and Doris Day. The author's hand looms large in the piece. We see him both as a boy and man - from schoolboy ingenue to inveterate devotee - as he looks back at a life populated with love, sex, drugs and death played out against a backdrop of crucifixes and power chords.