Mick Wall moves on from Led Zeppelin to produce a definitive doorstop on Metallica. Alongside contemporaries Slayer, Megadeath and Anthrax, Metallica came to prominence in the eighties as one of the 'big four' of thrash metal. Metallica were to thrash, though, what the Sex Pistols were to punk. Nearly thirty years on, their tale is one of alcohol, rule breaking and tragically early death. But allied to that are colossal sales figures for their records  they are the fifth-highest selling recording artists of all time  and members with backgrounds that touch on jazz and classical music. Metallica, in fact, have garnered more critical acclaim than any heavy rock band since Led Zeppelin.