"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."

As the rock world and fans alike mourn Ozzy Osbourne's death at age 76, some of his peers teamed up to pay tribute.

Fans at London’s O2 Arena got more than they bargained for when Johnny Depp made a surprise appearance during a high-voltage Ozzy Osbourne tribute.

Depp and Cooper performed Black Sabbath's "Paranoid" during a sold-out show at the O2 Arena in London on July 25

The US groove metal veterans learned about Osbourne’s death mere minutes before taking the stage in Austria on Tuesday