Character mistake: In isolation, Tony mentions John Travolta and says that he's known as the "king of cool." That nickname referred to Steve McQueen, not Travolta. (00:15:10)
Continuity mistake: When Gibbs is on the phone with DiNizzo, Tony's phone jumps from his right hand/ear to his left between shots. (00:05:35)
Continuity mistake: When Gibbs is comparing McGee to the FBI agent's ID badge, Gibbs' left hand disappears from the bottom of the badge. (00:16:10)
Continuity mistake: When McGee shows Abby the video, the first time it starts at 0:38, and when he shows it again it starts from 0:50. (00:19:00)
Plot hole: For such a dangerous serial killer, Lt. Cobb should be more securely restrained than he is. He wears a simple pair of handcuffs, with only one security escort.
Visible crew/equipment: In one of the first episodes (2nd or 3rd) of Season 1, in an interrogation room scene, the camera pans around the table, and a crew member is visible in the far wall mirror, standing beside the camera in front of Gibbs.
Factual error: While the NCIS crew are working a crime scene, Ducky starts yet another parable about his past experiences, referring to the dating of an Indian skeleton by the caliber of the bullet, "a 40-75". He states that since he knew the year that the US Army used that caliber, he could accurately date the remains. Unfortunately for Ducky, the US Army never used a 40-75. It did, however authorize a contract for a 45-70 cartridge in 1873. (00:09:20)
Continuity mistake: When Ziva dumps the four bundles of $100.00 bills on the bed, they all land face up. Then the scene changes to Tony taking a picture of them. Back to the bundles, and now only three are face up and one is face down, with no one touching them. (00:10:40)
Continuity mistake: When DiNozzo is on the phone at McGee's desk, he is fiddling with something that is on an open folder/file of a suspect. When the shot changes, this item has gone. (00:15:20)
Continuity mistake: Gibbs says about the waitress taking things personally in the diner. When he says this, he gestures with his thumb, which turns into an index finger in the shot without time to switch. (00:12:20)
Continuity mistake: When Gibbs and his dad are driving and Gibbs asks if his dad has eaten since yesterday, his arm is either out the window or down by his side depending on the shot. (00:10:50)
Continuity mistake: At the start, when DiNozzo is explaining what's up with Gibbs, McGee has his hands on his keyboard as if typing. When the shot changes, he's now moving his keyboard by the sides. (00:03:00)
Continuity mistake: The way McGee holds the phone for Daniel to look at the code changes between shots. Note his thumb. (00:13:30)
Continuity mistake: Towards the end, Gibbs shows the suspect a photo of the victim on the floor. However, when he asks where Marie is, the photo has gone. (00:34:30)
Continuity mistake: When Gibbs is doing the interview near the end, he puts a photo on the desk. When the shot changes, the gap between the photo and the edge of the table is significantly reduced. (00:33:40)
Continuity mistake: McGee is asked if he's looking to move to the private sector, and his hand is not by his chin. When the camera changes, his hand is now on his chin. (00:19:40)
Continuity mistake: When we see McGee in the interrogation room for the first time, he has his hands clasped in front of him. When the shot changes, his hands are lowered. (00:18:30)
Continuity mistake: When being questioned, they put a picture on the table in front of Ziva. In this shot, she has her arms on the table, palm up. When the shot changes, her hands are now palm down. (00:21:20)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.