Leave it to Metallica to do the unexpected even when they do the expected. It had been known -- advertised, even -- that the band would perform their 'Black Album' in its entirety on their European tour, which kicked off Monday (May 7) in Prague. They even brought back the "Snake Pit" to make it even feel as close to 1991 as they could.

However, what nobody could have anticipated was that they would play the album backwards. That's right, backwards. They opened the concert with classics like 'Master of Puppets,' 'The Shortest Straw' and 'Blackened.' Then, instead of the dramatic opening strains of 'Enter Sandman,' which was No. 31 on our countdown of the Top 100 Classic Rock Songs, they launched into 'The Struggle Within,' the album's closer and finished the set with 'Enter Sandman.' A three-song encore of 'Fuel,' 'One' and 'Seek + Destroy' followed.

"What a great show here in Prague to start off the 20th Anniversary of the Black Album!," a post on their tour journal read. "The band surprised everyone, and played it backwards! During and after 'Sandman,' it was pyro, pyro, pyro, and pyro!!! Sandman had 'fireworks,' 'Fuel' had the big flames, 'One' had the big booms and bangs, (including the new lasers) and the set ended with 'Seek,' with beach balls and more big pyro! Full setlist is up, pics to come!"

We admit that's a clever thing for Metallica to do. Not only does it force the audience to listen to the album in a different way, but it also solves the logistical question of how to play the album in its entirety and still save the biggest hit for the set closer. Metallica repeated the stunt in Belgrade, Serbia with a setlist that was identical, except for 'Battery' replacing 'Blackened.'