Hyspero has been ruled for thousands of years by the Scarlet Empresses, creatures of dangerous powers -- powers that a member of the Doctor's own race is keen to possess herself; the eccentric time traveler and philanderer Iris Wildthyme.
The Doctor and Sam themselves must escape the clutches of the dying Scarlet Empress, and they encounter many strange creatures on their travels -- bearded ladies, humanoid mock turtles, transvestite cyborgs and many more -- but in a land where the magical is possible, is anything really as it seems?