Factual error: In the yacht rescue scene the "American" crewed helicopter is actually an Australian crew. The rank on his shoulder shows an Australian Lieutenant Commander. (00:34:30)
Audio problem: When Tony is speaking with the commander on deck, he says he is waiting for "the next aircraft." But his lips don't match the words. (00:11:46)
Answer: I hadn't seen the backdoor pilots yet but while it wasn't explicitly stated, at least onscreen, I heard somewhere Vivian got either fired from NCIS due to jeopardizing a case, got resigned from the agency, or transferred to the FBI.
Raykvega423