NEW YORK CITY, NEW YORK: Actor David McCallum, who rose to fame as a teen heartthrob in the 1960s hit series 'The Man From U.N.C.L.E.' died at the age of 90 on September 25, 2023, from natural causes.

McCallum is survived by his wife Katherine Carpenter.

McCallum has two children—Peter and Sophie—from his second marriage with Carpenter and three sons—Paul, Jason, and Valentine—with his first wife Jill Ireland.

The actor's adopted son Jason died from an accidental overdose in 1989, which he lamented for the rest of his life.

David McCallum shared his son Jason's tragic loss in his own words

Jason David McCallum, adopted by McCallum and Ireland, was found dead at his Laurel Canyon residence in 1989.

His tumultuous life and struggles with drugs and alcohol had been the subject of Ireland's book 'Life Lines.'

27-year-old Jason, struggling with drug addiction, was found dead on the toilet floor of his rented flat by his girlfriend Tracy Medina, per Los Angeles Times.

The 'NCIS' actor rarely talked about his tragic death, although he had recently opened up to share his grief at the unfortunate circumstances.

McCallum previously opened up on his son's death to the Belfast Telegraph, "You never come to terms with the death of a child. The pain is very real, but it's like an ache that turns into anger."

"At the same time, there’s a frustration that you couldn't really have done anything about it, which makes it even worse," he said.

The Scottish-born actor continued, "In the final analysis, he had the life he had. You just have to accept it."

Ireland claimed in 'Life Lines' that Jason struggled with cocaine, alcohol, and heroin since his teens and had made repeated vain attempts to become better.

His ongoing addictions seemed to reflect Ireland's own ongoing battles with cancer, which she was diagnosed with five years before. But she admitted that Jason's had been more agonizing for her of the two struggles.

Following the disaster, McCallum stated, "The tragedy still haunts me. Jason got in with a certain type of showbusiness people and there was a drug culture going on and it killed him."

"I will always regret not being able to help Jason. He was one of the most wonderful people you could hope to meet," McCallum added at the time.

David McCallum overcame tragedy to become a beloved household name

In the 1960s, McCallum rose to fame as a young heartthrob on the famous show 'The Man From U.N.C.L.E.' and played the eccentric medical examiner on the hit 'NCIS' 40 years later.

Scottish-born McCallum has been having success with roles in movies like 'The Great Escape,' 'The Greatest Story Ever Told,' and 'A Night to Remember.'

However, the blond actor with the Beatles-inspired hairdo became a household name in the middle of the 1960s owing to 'The Man From U.N.C.L.E.' per Daily Mail.

In 2003, McCallum made a comeback on television in another series with the CBS program 'NCIS,' an organization known by its initials.

He portrayed Dr Donald "Ducky" Mallard, a pathologist who worked for the Naval Criminal Investigation Service, a division that looked into crimes involving the Navy or the Marine Corps.

Two Emmy nominations came from McCallum's work on 'U.N.C.L.E.,' and he received a third for his performance as a schoolteacher battling alcoholism in the 1969 Hallmark Hall of Fame drama 'Teacher.'

He played the titular character in the brief science fiction series 'The Invisible Man' in 1975, and he played Steel in the British science fiction series 'Sapphire and Steel' from 1979 to 1982.

McCallum also had several cameo appearances over the years in TV shows including 'Sex and the City' and 'Murder, She Wrote.'

He made his Broadway debut in 'The Flip Side' in 1968 and in the Michael Sheen and David Suchet-starring production of 'Amadeus' in 1999.

A statement released by CBS reads, "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."

McCallum, a lifelong American citizen who spent most of his time in the country starting in the 1960s, told The Associated Press in 2003 "I have always loved the freedom of this country and everything it stands for. And I live here, and I like to vote here."