Revealing mistake: Callan chases bad guy Ethan through the yard. Ethan runs down a set of stairs and towards the camera, before hiding between tanks. While running, Ethan's face is fully visible and it is very clear that it is not actor Charles Esten.
NCIS: Los Angeles (2009)
2 revealing mistakes in season 1 - chronological order
Starring: Chris O'Donnell, Linda Hunt, Barrett Foa, Daniela Ruah
Continuity mistake: When Deeks is shot in 2-17 "Personal", his records show no next of kin. However in later episodes he has a mother.
More trivia for NCIS: Los Angeles