Kevin Winter/WireImageThe 2015 Grammys opened up with a throwback!
AC/DC hit the stage to kick things off in a big way. The classic rock group showed off their impressive enthusiasm, performing first "Rock or Bust" and then "Highway to Hell," to an overwhelming audience reaction. Plenty of stars, including Blake Shelton, Lady Gaga, and Katy Perry, were rocking out with huge smiles on their faces.
And, the band also took a page out of Pharrell's book. Guitarist Angus Young displayed a similar look as the "Happy" singer by wearing shorts on music's biggest stage. As much as we wonder what Pharrell has to say about that, it should be noted that Angus has been rocking his schoolboy shorts look for approximately 45 years.
Also notable about AC/DC's performance was the fact that a former bandmember subbed in. Drummer Chris Slade, who played with the band from 1989 to 1994, stepped in to replace Phil Rudd, who's currently in the midst of some major legal woes. But, the group played together so seamlessly that the change was barely noticeable. It must be like riding a bicycle.