In 1978, while collecting documentary photographs of the artists' community in Montparnasse from the first decades of the century, Billy Kluver discovered that some previously unassociated photographs appeared to be related. The photographs, showing Picasso, Max Jacob, Moise Kisling, Modigliani, and others at the Cafe de la Rotonde and on Boulevard du Montparnasse, all seemed to have been taken on the same day. But the identity of the photographer and the occasion being recorded remained a mystery.

Investigation eventually allowed him to identify the photographer as Jean Cocteau and to determine the day that Cocteau had taken the photographs: August 12, 1916.

In a tour de force of art historical research, Kluver then reconstructed the precise scenario to which Cocteau's camera bore witness. With an investigator's eye for detail - noting when Picasso no longer carries an envelope or Max Jacob has acquired a decoration in his lapel - Kluver recreates a single afternoon in the lives of Picasso and friends.

Besides the central "portfolio" of photographs by Cocteau, the book contains additional photographs and drawings, short biographies of all the subjects, and a historical section on the events and activities in the early-twentieth-century Montparnasse art world.