Blessed with as many lives as a cat, not only have the protean "Priest" undergone nearly seasonal lineup changes, but on numerous occasions they have completely reinvented their sound to keep up with shifts in public taste. Originally deeply immersed in Progressive Metal elements (composing epic fantasy narratives in song), they soon switched roles from Conan-rockers to leather-clad, would-be Hell's Angels. Focusing their power into smoking, twin guitar testosterone fests, Judas Priest's Stained Class and Hell Bent for Leather catalyzed the so-called New Wave of British Heavy Metal. Once the arrival of Metallica and other Speed Metal acts made the Priest's mid-tempo, work-the-body assault sound outmoded and irrelevant, the band again huddled together and came up with a new game plan. They came out swinging, hoping for a swift KO. Painkiller (1990) was a blue ribbon entry in the Thrash category, much faster and heavier than anything else in the band's career; but when the album's tepid reception helped precipitate lead singer Rob Halford's defection from Judas Priest, the band's final transformation was already afoot. The remaining members hired themselves a new vocalist and, with a magician's finesse, turned a nine-lived cat into a chicken with its head hacked off.