CSI star Marg Helgenberger wasn't impressed when Bieber guest starred on the hit CBS show, calling him a "brat" in an interview with French radio show Le Grand Direct des Medias in May 2011. "He locked one of the producers in the closet," she recalled, "and he put his fist through a cake that was on the craft services table."
Bieber's response via Twitter?
"It's kinda lame when someone you met briefly and never worked with comments on you. I will continue to wish them luck and be kind."