'NCIS' Fan Favorite and Original Cast Member Returns for Season Finale

Sometimes it pays to have an old timer on the staff, and that’s what happens on tonight’s episode of NCIS when someone with a long—but good—memory is required.

It all starts when a body is discovered in the classified section of the National Archive, and NCIS must investigate a string of Russian spy encounters that may be linked to the crime. In fact, there are connections back to the last Russian spy ring that the team broke up that involved Senator Constance Miller (Brigid Brannagh).

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This time around, the team is able to figure out which file is missing, but since it hasn’t been digitized, it is unclear what exactly was in it and what the spy was looking for.

David McCallum<p>Photo&colon; Michael Yarish&sol;CBS</p>
David McCallum

Photo: Michael Yarish/CBS

That’s when Donald “Ducky” Mallard (David McCallum) pops into MTAC. Sorry, if you were hoping it was Gibbs (Mark Harmon), but we can hope that one will happen, too, in the not-too-distant future.

Ducky isn’t just the retired medical examiner, he’s also the NCIS historian, and so, he checks in from Edinburgh, Scotland, where he’s on city No. 14 of his 35-city lecture tour.

Luckily, he’s able to give them some background information on the man whose file is missing from the National Archive, who had defected from the Soviet Union and was trying to live a quiet life in the U.S.

And they even get in a fun reference to McCallum’s star-making role as secret agent Illya Kuryakin in The Man From Uncle.

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Then later in the show, when Ducky learns who was arrested for the murder in the National Archive, he issues a warning about “weapons of mass destruction,” which will take us into part two of the season 20 finale next week when Torres (Wilmer Valderrama) goes undercover to prevent an impending terror attack on U.S. soil.

McCallum, who will turn 90 in September, had posted a few years back that he was cutting back on work to “allow me to spend time with Katherine, our children, six grandsons and Nickie, pictured below!”

That was even before COVID, but during the pandemic it was impossible for him to make the commute from New York, where he lives, to Los Angeles for filming, so it is great to see him back—even if it is only via an MTAC video conference—for a second time this season as he was in person for the third episode of the season.

NCIS airs Monday nights at 9 p.m. ET/PT on CBS. And the good news is it has already been renewed for season 21 for CBS’ fall 2023-2024 schedule.

Next, CBS Announces its Fall 2023-2024 Schedule