Today’s Thrashback Thursday is a two-for-one deal. Metallica‘s Lars Ulrich and King Diamond (aka Kim Bendix Peterson) are Danish countrymen. The two have been close friends for some time. Metallica even recorded their breakthrough second album, 1984’s Ride The Lightning in the studio owned by King Diamond and his band Mercyful Fate.

So strong is Metallica’s reverence for Mercyful Fate that they have, for many years, been performing a medley consisting of several of the band’s songs (“Satan’s Fall,” “Curse of the Pharaohs,” “A Corpse Without Soul,” “Into the Coven,” and “Evil”) which they simply call “Mercyful Fate.” A recorded version of the tribute appeared on Metallica’s Garage Inc.

When Metallica made a stop in King Diamond’s adopted hometown of Dallas Texas in 2008, they invited the King himself to join them onstage to lend his iconic lead vocals to the medley. Check out the footage of that performance here below.