Ghost is a heavy metal band from Sweden that is recognizable for its on-stage appearance. Since the band formed in 2008, all members have performed with black hooded robes except the lead vocalist, who wears a Cardinal robe, a head piece and a skull mask. The identities and names of the band members are deeply shrouded in secrecy, as all the instrumentalists are referred to as Nameless Ghouls while the lead singer is called Papa Emeritus. Ghost released its debut single, "Elizabeth" in 2010, followed shortly after by the band's debut album, Opus Eponymous. The album has earned Ghost widespread attention from fans as well as other musicians, most notably Metallica's James Hetfield, who wore a Ghost t-shirt while playing a show in Sweden.