John Leeson, Voice of K9 on ‘Doctor Who,’ Dies at 83

John Leeson, the English actor who voiced “Doctor Who‘s” beloved robot dog K9, died on Sunday. He was 83.

Leeson’s son, Guy Ducker, announced his death in a Facebook post. “I regret to announce the death of my father, John Ducker, aka John Leeson, at 3:03 p.m. today after a summer of illness. The end was peaceful,” he wrote, adding the William Shakespeare quote: “Good night sweet prince: And flights of angels sing thee to thy rest!”

Leeson was best known for his voice work as the Doctor’s canine companion — who had the catchphrase “Affirmative, master” — on multiple seasons of British sci-fi series “Doctor Who,” spanning decades. He first voiced the character on the show from 1977-1981, when Tom Baker played the Doctor, and reprised the role in 1983 with Peter Davison in the lead; in 1993 for its 30th anniversary special; and in 2006 and 2008 during David Tennant’s reign.

Born John Ducker in Leicester, England, on March 16, 1943, Leeson attended the prestigious Royal Academy of Dramatic Art in London from 1962 to 1964, where he adopted his stage name. He started out in theater before transitioning to TV, guesting on sitcom “Dad’s Army” in 1969 and becoming a regular on the children’s program “Rainbow” as the furry bear Bungle.

But his work as K9 brought him the most success, resulting in several spinoffs including the TV movie “K-9 and Company” in 1981, sci-fi show “The Sarah Jane Adventures” from 2007 to 2010 and children’s series “K9” from 2009 to 2010.

In an Instagram post, “Doctor Who” writer and showrunner Russell T Davies remembered how when he decided to bring K9 back in 2006, “there was no question that we’d ask John to provide the voice, and it was impossible to imagine anyone else.”

“And really, what a performance, what a character: a posh dog, uppity, haughty, wry, but somehow innocent too, and so funny,” Davies continued. “’Maximum defense mode!’ God he was good. Pitched perfectly so that kids could impersonate him. That’s not easy, that’s hell of a piece of acting. And he was wonderfully dedicated to that character for… gasp, six decades! He’d phone me up and chat sometimes — on the landline, I remember, those were the days. Including one time when he hadn’t been paid! But he was so gracious about it. A true gent, and a great loss. Sympathy to his family and friends. Good night, sir. Affirmative!”