David McCallum, best known for playing Chief Medical Examiner Donald "Ducky" Mallard on NCIS, has passed away at the age of 90, several outlets have confirmed.
He passed away of natural causes at New York Presbyterian Hospital surrounded by loved ones. He turned 90 just last week.
The fan favorite NCIS character, who was a staple of the show since its very first episode aired in 2003, was set to reprise his role in the 21st season of the show, which had been delayed due to the WGA and SAG-AFTRA strikes.
Per Variety, a statement from NCIS executives Steven D. Binder and David North reads: "For over twenty years, David McCallum endeared himself to audiences around the world playing the wise, quirky, and sometimes enigmatic, Dr. Donald 'Ducky' Mallard.
"But as much as his fans may have loved him, those who worked side by side with David loved him that much more. He was a scholar and a gentleman, always gracious, a consummate professional, and never one to pass up a joke.
"From day one, it was an honor to work with him and he never let us down. He was, quite simply, a legend. He was also family and will be deeply missed."
Another statement from the network and NCIS studio CBS reads: "We are deeply saddened by the passing of David McCallum and privileged that CBS was his home for so many years.
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"David was a gifted actor and author, and beloved by many around the world. He led an incredible life, and his legacy will forever live on through his family and the countless hours on film and television that will never go away.
"We will miss his warmth and endearing sense of humor that lit up any room or soundstage he stepped onto, as well as the brilliant stories he often shared from a life well-lived. Our hearts go out to his wife Katherine and his entire family, and all those who knew and loved David."
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CBS is set to air a marathon NCIS special tonight in honor of the show's milestone 20th anniversary, and it is reported that the special will now include an "In Memoriam" card honoring McCallum.
Apart from his stint on the CBS crime procedural drama, McCallum was best known for long and illustrious film and TV career, with notable highlights being the 1963 film The Great Escape, playing Illya Kuryakin from 1964-68 on the spy series The Man From U.N.C.L.E., and his work as a composer throughout the '60s and '70s, most notably on TV soundtracks.
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The English actor was married to Jill Ireland from 1957-1967, with whom he had three children (one of whom died in 1989), and since 1967, he was married to Katherine Carpenter, with whom he had two more children. McCallum is survived by his wife, four children, and six grandchildren.