 Carlsen joins forces with Dr. Hans Fallada, a scientist researching energy vampirism and longevity, to find the escaped vampire and recapture her.In the course of their investigations they discover that the aliens can transfer from one body to another, and that the other two have also escaped; they also discover the potential for energy vampirism – and more generalised voluntary energy transfer – that exists in all humans, and the parallels between vampirism, criminality, and sexual fetishisation.At last Carlsen tracks down the vampires in London, their leader having possessed the body of the Prime Minister; but their confrontation is averted when representatives from the Nioth-Korghai, the vampires' original race, appear and offer the vampires (the Ubbo-Sathla, as they call themselves) the chance to regain their original nature as higher-dimension energy-beings.