 Although labelled as Science Fiction by the publisher, the bulk of the novel owes more to the thriller style of the John Buchan tradition, as the Cambridge hero battles across wild Irish landscapes fighting a series of murderous thugs and secret policemen.The science fiction denouement is confined almost to the last chapter and foreshadows the theme of Hoyle's later "A for Andromeda", though in a far more cursory manner.Also of note is the way the young hero seems to come to accept the notion of an authoritarian society ruled by a few self-appointed "supermen".