The Four
The Scientists are a group of alien humanoids from the planet Nekros, and are one of the main enemies of the Doctor. They derive their name from the experiments they perform on the corpses of sentient living organisms that have died in fear or pain. This is the main factor for the Doctor's intense hatred of them. Their first appearance will be in Time's Wasteland. They frequently employ what they call 'antibodies', actually the reaminated corpses of their experiments with genetic enhancments and inhibitions, much like the Daleks. They once formed an alliance with the Daleks, but both species betrayed each other due to their belief in universal superiority. In the future timeline desgnated as Earth-115 they had taken control of their neighbouring galaxies but had dwindled to a weak and life-support-system bound race.