"Justin Bieber wasn't bad," Helgenberger said. "He had never acted before. I shouldn't be saying this, but he's kind of a brat. He was actually very nice to me, but he locked one of the producers in the closet. And he put his fist through a cake that was on the table."
And that wasn't all Marg had to say.
"I am pretty open to whoever comes on the show," Helgenberger went on. "If someone is a jerk, that bothers me. If they're a so-so actor, it doesn't bother me. [Bieber] is actually better than you'd think!"
Coincidentally, the "Baby" crooner has been going onabout his love of a good prank all day on Twitter.
"Even when you arent feeling well a good prank feels sooo good. #pranksterontheloose," Bieber tweeted Sunday.
It's probably safe to say Marg doesn't feel the same.