Justin Bieber seem to be appealing surprised so as to "CSI" celebrity Marg Helgenberger tell a radio show he was a "brat" on the set ... particularly since they by no means actually work together.
Bieber now went to his Twitter page and with no mentioning Marg by name ... said, "it's kinda lame when an important person you met briefly and never worked with comments on you. I will continue to wish them luck and be kind."
