Long ago in an ancient land known as England, a group of musicians made a name for themselves by thrilling audiences with songs of death, destruction, and horror. They called themselves Black Sabbath. But every legend has to start somewhere. Before paranoid, before sabbath bloody sabbath, even before their eponymous album; Osbourne, Iomi, Butler, and Ward recorded a demo with legendary BBC radio announcer and music industry gatekeeper John Peel. This episode of the reference desk is about that demo, known to mortal men as… Walpurgis.