During an interview aired on radio station Europe 1, CSI: Crime Scene Investigation actress Marg Helgenberger was asked about Justin Bieber's guest appearance in the crime drama. Apparently the teen pop star wasn't entirely a pleasure to work with.

"I shouldn't be saying this, but he was kind of a brat," she says. "He was very nice to me. But he locked one of the producers in a closet and he put his fist through a cake that was on the cast's table." In the Bieber episodes, which aired in February, he plays a homicidal character who ultimately gets gunned down after firing a gun at the cops. When questioned about his acting, Helgenberger was a bit more complimentary: "Justin Bieber wasn't bad bad," she says. "But he'd never acted before.... He was better than you'd think."

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