A lot of people must enjoy watching tawdry glamour and alienated youth. As soon as it was announced in March that Penelope Spheeris's cult The Decline of Western Civilization trilogy would finally be released on DVD, it immediately entered the Amazon pre-order chart. They can't all be musicians watching on the tour bus.

The three films certainly set a standard for realism and bleakness in rockumentary, probably only surpassed by the work of Lech Kowalski, chronicler of junkies and skinheads, whose grey DOA captured England in 1977, Year of Punk, and made the opening titles of The Office look like the colour sections of The Wizard of Oz. The original film follows LA's early punk scene, the second and most famous segment is a celebrated overview of late-80s metal in its Sunset Strip, poodle-haired pomp, and 1998's final instalment follows the lives of homeless street punks – in Rumsfeldian terms then, that'd be the known unknowns, the known knowns and the unknown unknowns.

The Punk Years (1981) gave audiences worldwide an early glimpse of what would soon become known as hardcore, the frantically paced West Coast variation on punk, in the hands of Circle Jerks and an early iteration of Black Flag. X, LA's great gothic rock'n'roll band, steal the movie, while the hapless, ill-fated Germs hurtle around the stage, the nearest they ever got to a career. It might be sunny but the kids are bored and angry. Spheeris, already experienced in filming live performance as a pioneer of promotional clips, knew she was on to a winner. "When something walks in your path, do something about it." She recognised something in punk straight away: "Growing up, I came from total chaos and that's what the punk scene was. I had to make structure out of chaos."