Visible crew/equipment: When the car pulls up at the very start a man can be seen crouching and holding a camera in the wing mirror. (00:00:10)
Visible crew/equipment: When Detective Kemp walks in and shows Quinn's sketch, Ziva says, "Looks like an older version of him," then as she points to the plasma screen, the boom mic dips into view at the top of the screen. (00:03:05)
Visible crew/equipment: When Ducky says he caught the medical examiner and is discussing their findings, a square stage light is reflected in his glasses. (00:20:00)
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