Incredibly, the Sisters of Mercy have not released any new music for twenty-one years. Their last release was a compilation entitled A Slight Case of Overbombing back in 1993, which featured one new song, and since then they’ve been silent. However, unlike My Bloody Valentine or Guns ‘N’ Roses, who also left epic gaps between records, creating a mystique that sustained them, The Sisters of Mercy have disappeared into the realm of myth or legend, forgotten by all but the most devoted few. But a cursory look at the period they were active shows that they were a Big Deal,…