WHEN David McCallum takes his grandchildren for a stroll through Central Park, strangers call him names. Sometimes it's "Illya", the Russian agent he played in the 1960s television series The Man from U.N.C.L.E. Other times it's "The Invisible Man", the action hero he played in the 1970s TV series. But mostly it's "Ducky", the forensics expert he plays on crime series NCIS.
The Scottish-born actor has crafted an intriguing character in Dr Donald "Ducky" Mallard, the bow-tie-wearing specialist whose scenes are mostly confined to the forensics lab of the Naval Criminal Investigative Service. For a role that largely involves imparting a wad of gruesome facts and theories to the younger, fast-talking agents (headed by Mark Harmon's Special Agent Leroy Jethro Gibbs), Ducky seems to have taken on a life of his own, with his back story playing out in forthcoming episodes.
"Ducky's about as far away from a British stereotype as it's possible to be," says McCallum from California, where the series is made. "He's a wonderful eccentric, although he doesn't think he is, other people do. He's also well educated and to have a well-educated person in an American television series, people tend to think that is some kind of anomaly."
Unlike the clipped English tone of his alter ego, McCallum's accent fluctuates between English and American, with a hint of Scottish brogue. But his allegiances lie firmly with the US, which he has called home since 1963. And although he voted for John McCain in the recent presidential election, he can feel the Barack Obama fever sweeping the nation.
"There is a sense of euphoria," he says. "It is an event in this country — a real event. What's happened here is amazing. What we now have to deal with is the reality of the politics and as that slowly sets in, there is a degree of pragmatism which I think is going to take the edge off a little bit. I'm a Republican but I still wish Mr Obama every possible bit of luck, because he's having to face a really desperate situation as far as the economy and everything is concerned."
Ducky, he says, is a Republican also.
"Oh yes, definitely! He's a person who believes in taking responsibility for his own endeavours and not asking the government to do anything for him — that's the kind of person Ducky is. I can't imagine him ever turning to liberal ideology."
One of the first British actors to practise the Method style of acting, McCallum immersed himself in the gory world of forensics in preparation for the part.
"I have done a full autopsy with the chief pathologist in the coroner's office here in Los Angeles. I also have been acquainted with the army pathologists and seen the work they do. So I've had as close to a hands-on experience as you can without interfering. There is a huge difference between a live body and a dead one and there is the whole forensic puzzle."
The core characters of NCIS began life as guest roles on the final episodes of 1990s crime series JAG, from the same creator, Don Bellisario. The new team worked so well together that there was no need for a pilot and NCIS was launched in 2003.
But a rift between Bellisario and Harmon led to Bellisario's departure from the set. While his name remains in the opening credits, he is no longer involved with the nuts and bolts of production.
"I've always thought that Don Bellisario is brilliant," says McCallum. "I thought his concept of what he did with this show showed someone that really knew how to deal with all the verisimilitudes of the business and produce a success … Well, Don has been gone for a couple of years and we have Shane Brennan, our producer, so basically it's back to business as normal. I like and work well with Shane. I sometimes miss seeing Don's face around but I miss him as a friend as much as anything else."
Not only has NCIS survived a potentially damaging change of guard, it managed to bounce back after the 2007-8 US writers' strike. The winning formula, says McCallum, is a combination of interesting characters and making each episode a self-contained story.
"Given that the statistics say that people don't watch every single (episode) of a series, it's better in a way that most of the stories stand on their own," he says.
The filming schedule leaves little time for indulging in that yearning of TV actors, the stage, but McCallum is content to spend most of the year away from Broadway and his beloved Manhattan, on set in California.
"There's something wonderful about this town — it's warm and slightly hedonistic, and that I do enjoy."
NCIS airs Tuesdays at 8.30pm on Ten.