NCIS
Premieres Tuesday, Sept. 25 at 8/7c
5 Behind-The-Scenes Facts From NCIS' "Decompressed"
Pauley Perrette actually inhaled helium from a balloon for her lab breakdown.
"Her voice was only slightly altered in editing," NCIS Writer Brendan Fehily wrote.
By viewing our video content you are accepting the terms of our Video Services Policy. © 2018 CBS Interactive. All rights reserved.