There is a dead body floating in the steel-blue waters of the Cabrillo Marina in San Pedro, California. OK, so it's not really dead, and it's not exactly a body. It's actually a glassy-eyed silicone figurine, a stand-in of sorts for one of the recurring guest stars on the CBS drama NCIS — whose services, it appears, will no longer be needed on that hit show.

Mark Harmon, back for a fifth season as intrepid special agent Leroy Jethro Gibbs, is on hand to inspect the coastal crime scene. Sporting a tweed blazer and a dark shirt over a quasi-military white tee, the silver-haired actor leads baby-faced costar Sean Murray (who plays special agent Timothy McGee, aka Probie) and the sultry Cote de Pablo (former Mossad agent Ziva David) along the pier to the "corpse."

When the actors break, Harmon bounds up the gangplank to dry land where he is stopped by a beefy, middle-aged man leaning on a walking stick who has been watching them rehearse. "Hey, how do you like San Pedro?" the man asks randomly. Ever the professional, Harmon answers but keeps moving. "Beautiful day," he says, flashing the kind of grin that Gibbs would only reserve for special occasions. "What's not to like?"

Good question. Though it may be the kind of perfect summer day — blue skies, ocean breezes, whispering palms — that makes most people want to play hooky, Harmon is happy to be back at work. Of course, it doesn't hurt that he's returning from a nine-week hiatus to find a new sense of tranquility (dare we say, Harmon-y?) on the NCIS set. "It's very calm here," he says, kicking back among the clutter of family photos, books, backpacks and DVDs (Comes a Horseman, Cool Hand Luke) he keeps in the lovingly restored 1972 Airstream trailer that serves as his home away from home. "Right now we're averaging 12-hour days, and we have scripts, and people are organized. We used to average 16-hour days. Not that anyone's complaining about that. But having scripts is important on any show. If you don't have them, then the carpenters can't build the sets. So far, so good."

It's a sentiment that seems to be shared by everyone hovering around Berth 31 at the marina. Among the NCIS cast and crew, there is a palpable sense of relief. "This season feels different because, as you know, there's been a change of administration. And I think it's been a healthy one," says David McCallum, the 73-year-old showbiz vet who plays medical examiner Donald "Ducky" Mallard.

He's referring to the tumultuous departure of NCIS creator and executive producer Don Bellisario, who steered the series through its first four seasons. In late April, TV Guide reported that Bellisario's penchant for micromanaging and delivering scripts late had added undue pressure and longer hours to the grind of production and caused a rift with the usually affable Harmon. Weeks later, it was announced that Bellisario, who was also behind such TV classics as Magnum, P.I. and Quantum Leap, would relinquish his role, leaving NCIS in the hands of longtime coexecutive producer Chas Floyd Johnson and former head writer Shane Brennan (now both executive producers).  "Things are terrific [this season]," says McCallum. "We started at 7:30 this morning. Last year, we would have started at 7:30 tonight. There was always a certain degree of chaos, but it's all gone now."

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