‘NCIS: L.A.’ Showrunner Shane Brennan Reveals the 4 Secrets to the Show’s Success

This story first appeared in the Oct. 18 issue of The Hollywood Reporter magazine. 

Who would have thought a spinoff of a spinoff would reach 100? 

NCIS: Los Angeles, the No. 2 drama behind CBS juggernaut NCIS, has managed that feat. In 2009, NCIS: LA debuted as a two-part episode of NCIS (itself a spin­off of the successful 1995-2005 series JAG), introducing the sunny world of the L.A.-based Office of Special Projects, a division of the Naval Criminal Investigative Service that specializes in undercover ops. Big names Chris O'Donnell and LL Cool J were immediately attracted.

"I became fully aware of just how tough it is to get a show to 'work,' having had a few misfires in previous years," says O'Donnell, 43, who plays Special Agent G. Callen, likely referring to his failed 2005 Fox comedy Head Cases. "Todd [LL Cool J] was in the same boat, and we looked at each other and said, 'Let's do everything we can to make this work. We know it's a crapshoot, but let's not have any regrets over preparation or focus.' "

The focus paid off. NCIS: LA has averaged more than 18 million viewers in the past three seasons, according to live-plus-7 data. "Fortunately, people responded to the chemistry on the show," O'Donnell says of the ensemble, which includes Linda Hunt. "As Todd says, 'Teamwork makes the dream work.' "

Creator Shane Brennan, who also ran NCIS, shares four tips that have kept NCIS: LA fresh.

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1. KEEP IT RELEVANT

NCIS: LA focuses on military crimes, which means the writing staff keeps up on current events, both domestic and abroad, for story ideas. Sometimes they're ahead of the game: Early episodes included a chemical technology that Feds sprayed on suspects to identify them -- its real-life counterpart has since become classified -- as well as a plot centered on terrorist group Al-Shabaab, which in September claimed responsibility for a deadly Kenyan mall attack.

2. GROW THE CHARACTERS

"Characters have to keep moving," Brennan says, whether it's through breakups or big revelations. Eric Christian Olsen, who joined as a recurring guest star in season one as Detective Marty Deeks, made a big impression at the end of his three-episode arc -- in his "goodbye" scene to Junior Special Agent Kensi Blye (Daniela Ruah), he was insouciantly resting on a car hood: "Fans really liked that and began asking, 'When is he coming back?' "

The mystery of G. Callen's identity remains a compelling question, which Brennan promises is partially answered in episode 100. "It's Chris O'Donnell's best work yet."

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3. DO NOT CHEAT LOS ANGELES

Brennan told location managers at series launch that he wanted to film "at every iconic L.A. location" possible. Since 2009, NCIS: LA has featured Venice Beach, the Walt Disney Concert Hall and the legendary Hollywood Bowl. "People in L.A. can identify when locations are fake," Brennan says.

4. NEVER FORGET YOU'RE THERE TO ENTERTAIN

Probably "40 percent of TV on broadcast is procedurals," Brennan says, "so you're competing with others." How to stand out? "One of the ways NCIS: LA is different," says Brennan, "is it's played out in the high stakes arena of national security." He also relies on character growth and storylines: "I think we're the best at doing that."

Philiana Ng