Justin Bieber lip-syncing in a wig to Ozzy Osbourne is the most disturbing thing you'll see all day

Brace yourselves, metalheads.

Justin Bieber has slapped on the eyeliner and a black wig to lip-sync to Ozzy Osbourne's 1980 hit 'Crazy Train'. Yes, really.

Watch the disturbing video above from Spike TV's Lip Sync Battle to witness the horror.

Then re-live the moment Ozzy, 66, had no idea who Justin, 21, was in the 2010 interview below…

Hey, it is Flashback Friday after all!