The Family of Blood

Home Planet: Unknown
Life Form: Incorporeal group mind

The Family of Blood were green, gaseous entities that could inhabit and control Human bodies. Before taking human form, the members of the Family of Blood were kept in small, spherical receptacles. They had very short-lifespans, lasting only 3 months. The members that were chasing the Doctor were made of a mother, father, son and daughter. While in Human form the Family could telepathically communicate together from a distance. They also had incredible sense of smell, tracking The Doctor with his scent. They also had access to the Host's memory, though they had some difficultly pretending to be Humans. The Family had a spaceship, with various features. They used technology to render their craft invisible to Humans. The Family also had scarecrow-like soldiers created by the son and placed into various fields. The Family encountered the Doctor and Martha Jones in 2007 and chased them throughout time and space with a stolen Time Agent vortex manipulator in order to steal from the Doctor some means of ensuring that they would live a longer lifespan. The Doctor was forced to turn himself into a Human using the Chameleon Arch in his TARDIS in order to escape them. The Doctor changed himself into John Smith, a teacher at a boy's school in England in 1913. The Family's quests for immortality ended when the Doctor was returned to his Time Lord state with the help of Martha, school nurse Joan Redfern and the telepathic Timothy Latimer. He fooled the Family with an olfactory misdirection and destroyed their spaceship by moving several switches in an act devised to look like an accident, destroyed the ship.

Episodes: Human Nature, The Family of Blood