If you didn't know, there were two Black Flags: one fronted by nasal-toned Keith Morris and the other by throaty Henry Rollins. This classic collection of unreleased songs from 1978-1981 is essential. "I Don't Care" could easily be the most important 58 seconds of punk rock history, and Rollins' take on the frat-rock classic "Louie Louie" sounds like he's gargling glass.