Fans of NCIS were left “heartbroken” when David McCallum’s character - Dr Donald - was killed off after the late star’s death.

Monday’s installment of the CBS crime series marked the beginning of the 21st season and also the sad end of Dr Donald ‘Ducky’ Mallard’s storyline. Towards the final scene of the exciting episode, Agent Nick Torres - Wilmer Valderrama - frantically asked Agent Alden Parker - Gary Cole - what was going on, and viewers knew things didn't look good for Dr Donald. We were all left in suspense as the episode cut off on a cliffhanger, but sources later confirmed that the next episode would confirm the death of 'Ducky'.

David had played the beloved medical examiner-turned-historian throughout the whole 20 seasons of NCIS - starring in the 2003 pilot of the iconic series. The actor sadly died in September last year at the age of 90.

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David has starred in the series since it began (
Image:
getty)

Fans were left bereft when TV Line confirmed on Monday that the unsaid news Nick got from Alden was that Dr Donald had died. They took to social media to share how sorry they were to see ‘Ducky’ go.

One fan wrote on X: "Not ready for #NCIS next week. We all knew they’d write it in somehow with the actors passing but I’m still not ready for Ducky to go.” Another wrote: "The farewell Ducky episode is next week! Not sure I’m ready for that!!!"

Fans were "heartbroken" at the thought of never seeing Dr Donald on our screens again (
Image:
getty)

The seasoned actor, who was born in Glasgow, Scotland, died from natural causes and was surrounded by family members in his final moments. Earlier in his career, David starred in the 1960s spy fiction series The Man From U.N.C.L.E.

Following his death, NCIS executive producers released a joint statement about the passing of the longtime star. They said: “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.”

David was described as a "legend" with a great sense of humor (
Image:
getty)

They went on to describe David as a “legend” with a cracking sense of humor, adding: “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.”