Why is one episode of NCIS, a forensic murder mystery with a military setting, more popular with young viewers than an entire season of Mad Men? The JAG spinoff, in which Mark Harmon investigates crime in the U.S. Navy and Marine Corps (Tuesdays on Global at 8 p.m.), has seen steadily rising ratings since it premiered in 2003; this season, it became the No. 1 show on TV and launched its own spinoff, NCIS: Los Angeles. But it’s also in the top 10 among the 18 to 49 age group, and gains an extra two million viewers from new-media formats. Shane Brennan, who runs NCIS and created the spinoff, says that there are even “college parties where they sit and watch NCIS reruns.” How did this show become cool when no one was paying attention? Maybe because it’s not a procedural like CSI; one of NCIS’s stars, Michael Weatherly, described it to the Los Angeles Times as a throwback to Barney Miller. NCIS is secretly a sitcom with dead bodies.

Brennan, who has also worked on CSI: Miami (as well as the teen drama One Tree Hill), says that other procedural shows spend a lot of time “putting the clues together in a scientific way.” NCIS spends less time on science and therefore has “more time to develop character.” The mysteries on NCIS are sometimes perfunctory or pointless. A recent episode had Agent Gibbs (Harmon) solve the crime at the last minute without explaining how he figured it out; the culprit was a guest character who had only one scene in the episode (and who, inexplicably, confessed right away). Brennan says that on NCIS, “it really doesn’t matter so much what the story is: it’s how the character reacts.” That makes it different from shows where the characters are secondary to plot twists, or procedurals like Law and Order, where topical issues dominate. NCIS has more in common with young-skewing comedies like The Big Bang Theory, which also has simple plots. Like those shows, NCIS is an excuse for viewers to hang out with characters they love. Continue…