In 2017 Dr Rupert Aston is a clever and conscientious hospital consultant who has been asked by a colleague to sort out the illness of a particularly difficult patient. While he tries hard to get to the bottom of the clinical problem, he is bequeathed a suitcase by his late father containing a mysterious personal journal written by a distant medical ancestor called Dr William Aston, a prominent London physician practising in 1768. His ancestor also describes an intriguing patient whose case baffles all the medical doctors looking after him. As he reads the journal Rupert becomes increasingly aware of the strange similarities between the two cases despite the appallingly stark contrast in medical practice and attitudes between the two time periods. The narrative alternates between subsequent events in contemporary London and Georgian London until Rupert eventually reaches a credible diagnosis with the aid of one of his colleagues. While his patient is slowly improving with modern treatment, Rupert is made aware of an extraordinary sequence of events that shakes him to the core. He has to decide for himself whether all that has happened is mere coincidence or whether everything that his rational mind has thought to be real has just been an illusion.