Hailed as one of dance music's first major album-length statements, Leftism recalls the anything-goes spirit of the mid-'90s, when the U.K.'s rave culture was opening up to new ideas. Trance-inducing tracks like "Black Flute" and "Space Shanty" paid tribute to long nights in muddy fields, but others—from the sci-fi chirps of "Release the Pressure" to the ambient synths and spoken word of "21st Century Poem"—had wider vistas in mind, including world-music accents and even a John Lydon cameo. Breakbeat-laced cuts ("Storm 3000"), meanwhile, introduced the world to a quintessentially British take on techno.