The first part of the opening scene in Gibbs' shop is meant to be the same moment shown at the end of "Rule Fifty-One". However, it has clearly been re-shot. In the previous version, Mr. Gibbs faces (the yet-to-be-revealed) Reynosa with a smile and a happy "Can I help you?" Here, he stands sideways to her, no smile, and asks the same question with suspicion.
When Alejandro is led into the safe house after shooting Paloma, he kneels next to her and she strokes the right side of his face, leaving three finger trails of blood across his cheek. A few seconds later, when the camera very briefly shows the same side of his face as he looks up at Gibbs, there is only a single spot of blood on his cheek.
RCMP officers only wear their Red Serge dress uniform during ceremonial duties; they would never be worn while investigating a crime scene. The same is true for the 'Mounted' part of their name - only the 32 members of the Cavalry unit who participate in the Musical Ride are mounted. The concept of having RCMP officers mounted on horses in their Red Serge on daily operations is beyond laughable - simply stereotypical, along with the idea that there was snow in September just north of the US/Canadian border.
When McGee and Tony are talking in over video whilst McGee is in Canada, Mcgee says 'it's September, there's snow on the ground'. You can clearly see there is no snow on the ground or trees and the weather is clear and sunny. None of the Mounted Police are wearing cold weather gear.
When the cameraman has to cross a crime scene tape, it is visibly pulled down so he can cross without falling.
Agent DiNozzo incorrectly states that the Wonder Twins from Super Friends activate their powers by touching their rings together. The Wonder Twins did not have rings, simply touching hands to activate their powers.