|Apologies, Master. This page is about the robot character. For the TV series, see K-9.|
K9, also spelled out as either K-9, or K•9, is a fictional robot featured in the British television franchise Doctor Who. The robot was introduced in the original series as a companion to the Fourth Doctor, and has also been a loyal ally to the Doctor's humanoid companions as well. K9, throughout his various iterations, has also been associated with Sarah Jane Smith and, for a brief time, the Tenth Doctor as well. K9 has made appearances on the 2005 Doctor Who revival series, the spin-off series The Sarah Jane Adventures, and has also been the feature character in his own K-9 television series. On the original series, K9 was voiced by actor John Leeson.
- Refers to the Doctor as Master and calls the Doctor's female companions by the title Mistress.
- K-9 has been programmed with all championship chess games since 1866. 
K9 Mark I Edit
K9 Mark II Edit
- Voice of K9 redirects to this page. This is how actor John Leeson is credited in episodes of the original Doctor Who.
- The K9 designation is an obvious pun on the word canine, which is a subfamily which includes dogs, wolves, coyotes and hyenas.