Metallica’s Robert Trujillo and Kirk Hammett have been having fun lately with their nightly "doodle" segment -- where Lars Ulrich and frontman James Hetfield  leave the stage, leaving them to jam as a duo.  They tend to pull out covers of bands from the European city in which they are performing, but last night (May 2) in Oslo, Norway the pair took it to a whole new - and wholly unexpected - level when they took on the '80s classic "Take On Me" by A-ha.

"Try and guess what this is, and if you know it, sing it!" Trujillo says in a video clip, which can be viewed above, before going into the song. "Remember, this is fun - it's a party!"

The audience at the Telenor Arena in A-ha's hometown of Oslo were both surprised and elated at Hammett and Trujillo covering the song, which was a number one hit around the world in 1985 but undoubtedly holds a special place in the hearts of locals.

At earlier gigs in the tour they covered Michael Schenker Group’s “Into the Arena” and UFO’s “Rock Bottom” in Hamburg, Germany, Black Sabbath’s “War Pigs” last fall in Birmingham, England and they covered Oasis’ “Don’t Look Back in Anger,” at a Manchester, England gig, which occurred in the wake of the bombing at an Ariana Grande concert. Recent weeks have seen them take on the Accept classic "Balls to the Wall" in Leipzig, Germany, paid tribute to the late Celtic Frost bassist Martin Eric Ain in Switzerland with a cover of "Procreation (of the Wicked)" as well as German '80s star Peter Schilling's "Major Tom (Coming Home)" at a gig in Stuttgart, Germany.

Next up for Metallica is a two-night stand in Stockholm, Sweden at Ericsson Globe May 5 and 7 (surely on one of those nights they'll have to pull out ABBA's "Dancing Queen"). Then it's a handful of additional European dates before taking off for the summer and returning to the road in North America for a run of arena shows. The full list of upcoming dates can be found here.

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