Gritty rather than glam, this incendiary, cult classic both confounded and delighted audiences upon its release in 1975, at the height of the legendary glam-rock band’s success. Charting the rise of fictional rock group Flame, with Slade themselves playing the band, it offers a witty, sublimely cynical and warts-and-all view of the ‘70s rock-biz, stuffed with high-octane Slade boot-stompers.