Corrected entry: If the ship is that top secret that the Navy commander had to get permission from his superiors to brief the director of NCIS on the ship, its mission, and what it might be carrying, there is NO WAY, NO HOW that the United States Navy would allow an Israeli Mossad agent on board that ship.
Corrected entry: When McGee finds the baseball bat in the woods, he's bare-handed. In the next shot, he's wearing latex gloves on both hands. (00:17:00)
Bete Noire - S1-E16
Corrected entry: When Kate pretends to be Abby, trying to trick Ari, he deduces that she's not upon seeing her gun in its holster, and doesn't pick up on the more blatantly obvious fact that her manner of dress doesn't match Ducky's description of Abby as a Goth.
Correction: Well, considering the fact that Ziva is an NCIS agent, they probably overlooked the fact that she is Mossad and let her on. (Or the commander might not have known that she was Mossad.).