In answer to his least favorite question, James Hogan explained (in the Jan 2006 Analog) that the idea for this novel came from an all night conversation with Charles Sheffield about the classic time-travel paradox of what happens if you send something back in time and the arrival of that thing is the very cause of you not sending said thing back in time. Much of the novel is a similar conversation between physicist Murdoch Ross, his friend Lee, and Murdoch’s Nobel Prize winning grandfather Charles who has invented a way to send messages through time.

Professor Alymer Arbuthnot Abercrombie is on the verge of completing eight years of work to build a time machine when all of his vital notes are stolen.