Under the Volcano tells the story of Geoffrey Firmin, an alcoholic British consul in the Mexican city of Quauhnahuac, on the Day of the Dead in November 1939. The book consists of twelve chapters, the first of which introduces the narrative proper and which is set exactly a year after the events. The following eleven chapters happen in a single day and follow the Consul chronologically, starting early on the morning of the Day of the Dead with the return of his wife, Yvonne, who left him the year before, to the end of the last day. The book takes its name from the two volcanoes, Popocatepetl and Iztaccihuatl, that overshadow Quauhnahuac and the characters.