|Humphrey the Killer Plant|
|Played by||Christopher Thomson|
Humphrey is a Killer Planet that can morph into a humanoid appearance at will. He can eat people and pug dogs, but only when in a really bad mood; whether or not eating humans and pugs is necessary for his survival is never established.
Humphrey migrates to Planet Earth to find peace. After an incident with The Pompous Doctor, he ends up living in Perfectio Gardos, with two Cybermen and his friend Codsworth. He later joined an army of cameos to help several incarnations of The Doctor fight against an army of Daleks. When Perfectio Gardos was being disturbed by Giant Space Pugs The Quintessential Doctor helped keep the Pugs away from the planet, with Humphrey thanking her for her work.