In the small hours of January 1st, a man begins to write, having watched Le Grand Concert de la Nuit, a film in which a former lover - Imogen - plays a major role. For the next year, he writes something every day. His journal is a ritual of commemoration and an investigation of the character of Imogen and her relationships - with himself; with her family and friends; with other lovers. Imogen is an elusive subject, and The Great Concert of the Night is an intricate text, mixing scenes from the writer's memory and the present day, and scenes from Imogen's films, with observations on a range of subjects, from the visions of female saints to the history of medicine and the festivals of ancient Rome. But one subject comes to occupy him above all: what happens when a person becomes a character on the page.