the first thing i would like to say is that what common sense media says about this show(or really anything you see on this website) is their opinion, not the average opinion of everyone giving reviews, or the shows ratings (It was voted america's #1 favorite show over shows that they gave higher ratings like CSI).
Messages-The messages of all police procedural dramas is that there IS evil in the world, and that good will win in the end. NCIS is
Characters-The characters all have really different relationships, that are fun to see grow and expand throughout the seasons. At the end of the day they are there to help each other and anyone else who needs them
Violence-Though there are smaller plots intertwined throughout the season, it's a cop show. The show generally starts out with someone finding a dead body (occasionally it's someone getting killed or kidnapped) and the team has to find out who did it. There ARE guns and bombs, but not to the point where it's scary or too violent.
sex-sometimes it's part of the crime, sometimes part of the characters lives, and sometimes they make jokes about it, but it stays PG-13 at it's worst.
Language-there are swear words, not used to excess. These words kids already know, and know whether they're allowed to use them or not. no bombs dropped through out the show that i know of.
Consumerism-brand names are just as much as any other show, mentioned and visible.
Drinking, Drugs smoking- generally, if these are happening, it's part of the crime(trafficing drugs). occasional social drinking.
One of my favorite shows, but everyone has their own opinion. try it and see if you like it:)