In the future Earth is a polluted world, leading to humans evolving in to Haemovores. Haemavores display Vampire-like characteristics, such as a craving for blood and an immunity to bullets. They are not affected by sun-light, but they were repelled by psychic barriers, such as unswerving faith. The Doctor managed to repel a hord of Haemovores with faith in his former companions.
The seventh Doctor visited Earth during the Second World and met up with Dr. Judson who was trying to translate some ancient Viking inscriptions. When translated and read they would summon the evil entity known to the Doctor as Fenric.
In his battle with the Doctor Fenric summoned haemovores back in time to help find lost oriental treasures. The haemovores could survive under water and had tremendous strength. Once they were let loose they turned locals into pseudo-haemovores. Jean and Phyllis were two such victims.
- Furture Earth