"Pirates of the Caribbean" star Johnny Depp joined Alice Cooper on stage in London Friday to honor late rock icon Ozzy Osbourne with a performance of Black Sabbath's hit "Paranoid."

Inevitably, and rightfully, at their more-or-less co-headline concert at a busy O2 Arena, both Judas Priest and Alice Cooper found ways to memorialise their late comrade in metal, the pioneer Ozzy Osbourne,