The Rani, another renegade Time Lord, is an amoral biologist, interested only in the outcome of her experiments and not interested at all in any side effects they may cause.
The Rani enslaved the population of Miasimia Goria. In an attempt to make them more productive the Rani gave the population a drug, only it deprived them of sleep and turned them into savages. To remedy this the Rani regularly travelled to Earth and extracted the brain fluid from humans that promotes sleep.
By doing this the Rani was responsible for some of the most violent periods in human history, including the Luddite riots. It is here that the sixth Doctor and Peri first met the Rani, who was posing as and old bath house manager. When workers came in for a bath she would render them unconscious and extract the fluid.
The seventh Doctor and Mel later met the Rani on the planet Lakertya where she was planning to fire a rocket loaded with 'loyhargril' to destroy an asteroid of strange matter and turn Lakertya into a time manipulator.
- Kate O'Mara
- Time Lord