If modern politicians rely excessively on pollsters and spin doctors, what should we say of the trust which their medieval and Renaissance predecessors placed in diviners and soothsayers? Among the most famous of these latter practitioners was ‘Dr’ John Dee, born just six years before Henry VIII’s youngest daughter, who availed herself of his services even before she succeeded to the throne as Queen Elizabeth I. Alchemist, antiquary, astrologer, astronomer, geographer, magician, mathematician, political adviser, seer, spirit-raiser, and theorist of empire: the full dimensions and scope of Dee’s omnidisciplinarity are not easily conveyed. Dee moreover inhabited a world ‘saturated with magic [...] not so much a world that we have lost, but more a strange, unfamiliar place that few modern readers can imagine’, to quote his latest biographer.