"It's a lot to be the lead of a television show. It's a lot of responsibility and it's an honor, but you do have to set a tone for a set," Deschanel said, adding that it meant she was usually stressed out while doing the show. However, Boreanaz had a unique way of letting her know if she was being unpleasant — if someone on set brought her a Diet Coke, she knew she should tone it down.