Even on a hit series like NCIS, not every scene is easy for the cast. Over the years, several actors have opened up about filming moments that pushed their comfort zones, emotionally or physically. One notable example involves Cote de Pablo, who plays Ziva David. Early in her run, she had to film an intense autopsy scene with little time to prepare. The pressure of memorizing heavy dialogue overnight made it a stressful experience she never forgot.

Chris O’Donnell from NCIS: Los Angeles also faced his fears while filming a scene that involved diving into shark-infested waters. Terrified of sharks, he insisted a diver check the area before every take. He later admitted he bolted out of the water the second each scene wrapped—making it one of his most nerve-wracking experiences on set.

Another layer of discomfort came from behind-the-scenes tension. Pauley Perrette, who played Abby, had a highly publicized falling out with Mark Harmon after an alleged incident involving his dog. The situation grew so tense that the two filmed their scenes separately for her final season. It was a tough and emotionally charged situation for everyone involved.