A parasitic alien soul is injected into the body of Melanie Stryder. Instead of carrying out her race's mission of taking over the Earth, "Wanda" (as she comes to be called) forms a bond with her host and sets out to aid other free humans.
Kit, a troubled girl, is sent to the exclusive Blackwood boarding school, where she discovers that only four other female students have been admitted to learn the four pillars of knowledge under the ominous wing of the mysterious headmistress Madame Duret.
After waking in a park with total amnesia — and surrounded by dead bodies, all wearing latex gloves — a young woman must fight to uncover her past, and resume her position at the head of Britain’s most secret (supernatural) service before the traitors who stole her memory can finish what they started.