The apocalypse was supposed to happen in 2012, not 2013, right? It seems like doomsday math has always been a little off, so we have some evidence that might be more proof positive of the pending end of times than some number crunching. Pop sensation Justin Bieber was recently filmed singing along to a Metallica jam!

First Lady Gaga polarizes metal fans with her open love for heavy metal and now Justin Bieber. In a 2012 interview with GQ, Bieber stated that he is a fan of early Metallica and commented on 'One' and 'Fade to Black' simply stating, 'Those are my jams.' Well, the kid wasn't lying as evident by the video above, reported by NME. His musical director mans the acoustic while Bieber plays the air guitar and vocalizes the solo from 'Fade to Black.'

Of course, this is just a little backstage fun, but now we have to wonder if Bieber went to see the Metallica movie 'Through the Never' and rocked out harder in the theater. Was he standing on his seat playing air guitar and met with angry demands for him to sit back down or did other movie-goers join in with him? This is all wild speculation, but would be pretty funny to imagine.

Metallica drummer Lars Ulrich recently revealed that he would like to tour with U2 and Green Day, but maybe he should consider adding a fourth act to that lineup.