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Justin Bieber made his acting debut on "CSI" last year and one of the show's stars gave a scathing review of the Biebs' on-set demeanor.
"I shouldn't be saying this but he was kind of a brat [on the set]," Marg Helgenberger in an interview with France's "Le Grand Direct Des Medias."
"He was very nice to me," Marg clarified. "But he locked one of the producers in a closet."
According to Marg, the teen heartthrob's antics didn't stop there. She went on to allege that Bieber also "put his fist through a cake that was on the craft service table."
On the show Bieber played a troubled young man named Jason McCann, who was shot dead during a standoff in the CBS drama's season finale. Marg may have been disappointed by the singer's off-camera attitude, but she did compliment him on his performance on camera, saying, "He's actually better than you'd think."
"CSI" airs Thursday nights 9/8c on CBS.