K-9

K-9
Aliases	K-9 K•9
Species	Robot
First Appearance	The Invisible Enemy
Last Regular Appearance	Warrior's Gate
Main Actor	John Leeson
Other Actor(s)	David Brierly

K9 - occasionally written as K-9 or K.9 was the designation given to a series of intelligent dog-like robots who served as companions of Professor Marius, the Fourth Doctor, Leela, Romana and Sarah Jane Smith