emo serious! Ha!
Check out (above) a clip of Justin Bieber's guest-starring stint on CSI last night as a troubled teen!
We personally think T-Swizzle did a better job when she guest-starred on the show, but he DEFINITELY fares off a lot better than Bristol Palin did on Secret Life of the American Teenager!
What do U think?? Did you like Bieber's performance on CSI??