This is the story of the biggest selling heavy metal band of all time -- Metallica -- and the album that helped them become so -- known variously to their fans as 'Metallica', 'Untitled', or simply 'The Black Album'. Having revolutionised the very term 'heavy metal' in the Eighties, bringing it down from the spandex mountain it occupied, back to the street from which its ugly, twisted roots first came, Metallica began life in the Nineties as cult heroes.