Henry Lytten - a spy turned academic and writer - sits at his desk in Oxford in 1962, dreaming of other worlds. He embarks on the story of Jay, an eleven-year-old boy who has grown up within the embrace of his family in a rural, peaceful world - a kind of Arcadia. But when a supernatural vision causes Jay to question the rules of his world, he is launched on a life-changing journey. Lytten also imagines a different society, highly regulated and dominated by technology, which is trying to master the science of time travel. Meanwhile - in the real world - one of Lytten's former intelligence colleagues tracks him down for one last assignment. As he and his characters struggle with questions of free will, love, duty and the power of the imagination, Lytten discovers he is not sure how he wants his stories to end, nor even who is imaginary...