John Leeson, Voice of K9 in Doctor Who, Dies at 83

John Leeson, the English actor who voiced K9, the robot dog in Doctor Who, has died at the age of 83.

His son, Guy Ducker, announced the death in a Facebook post on Sunday, November 1, 2026. Guy wrote: "I regret to announce the death of my father, John Ducker, a.k.a. John Leeson, at 3:03pm today after a summer of illness. The end was peaceful. 'Good night, sweet prince, and flights of angels sing thee to thy rest.'"

Bleeding Cool, the entertainment news site, reported the family announcement on Sunday. Leeson is survived by his son, Guy, and his wife, Judy Griffiths, whom he married in 1969, according to Bleeding Cool.

Leeson was born John Francis Christopher Ducker on March 16, 1943, in Leicester, England. He trained at the Royal Academy of Dramatic Art, and his stage and television career spanned half a century.

The voice of K9

Leeson was first brought on as the voice of K9 for the 1977 Doctor Who story The Invisible Enemy, alongside Tom Baker as the Fourth Doctor. Producer Graham Williams liked the character so much that K9 stayed on as a regular character, according to Leeson's biography.

In a 2014 interview, Leeson described how the voice was built. He said Williams told him: "Well really K9 is the receptory and the deliverer of all information. He's an absolute know-all, but we want his voice to sound as if it comes out of a tiny little elliptical speaker in a cheap radio." Leeson said his own part was simple: "I just put up [my voice] a few levels, clipped it as much as possible, made it sound like a machine. It couldn't sound like a dog, because K9 isn't a dog, but I made it sound as mechanical as possible."

Leeson left the programme after the 16th season in 1979, worried that a voice only role would hurt his chances of other work. David Brierley voiced K9 for a time, and Leeson returned in 1980. He voiced K9 again in the anniversary story The Five Doctors, and in the spin-off K-9 and Company in 1981. When K9 returned in the 2006 episode School Reunion, Leeson was back in the role, which led to a recurring part in The Sarah Jane Adventures from 2007 to 2010 and a return in the 2008 episode Journey's End. He also voiced K9 in the spin-off series K9 and in Big Finish audio dramas, including Zagreus and the Gallifrey series, and he appeared as K9 in The Five(ish) Doctors Reboot in November 2013.

Work beyond Doctor Who

Before K9, Leeson played Bungle the bear in the children's programme Rainbow. His other television work included roles in Blake's 7, Dad's Army, Doctors, 'Allo 'Allo!, The Bill and Sorry!, and he worked as a continuity announcer for BBC Television and Channel 4. His autobiography, Flight of the Budgerigar, was published in October 2011.

The family announcement reported on Sunday gave no funeral details. Leeson voiced the character, on and off, from 1977 to 2010, on television and in audio plays.