Despite his young age of 24 at the time of publication, Eça de Queirós had already visited Egypt as a journalist for the Lisbon newspaper Diário de Notícias, to cover the inauguration of the Suez canal. The Mystery of the Sintra Road was initially published in Diário de Notícias, in the form of 66 letters to the editor that were reproduced in the serials section of the newspaper between July 24 and September 27, 1870. It was published as if it were a true story about an alleged kidnapping (with the knowledge of the newspaper's editor, Eduardo Coelho, who was a friend of Eça's family). The bet Coelho made with the two authors that only the last instalment would reveal to the readers the writer's identity was very successful. Portuguese readers were already familiar with serialized crime and detective novels, particularly from France and this serialization became extremely popular, despite being in part a parody of the French genre. It captured the imagination of and even frightened the people of Lisbon, many of whom thought it was describing true events, and resulted in copies of the daily paper being sold out. Despite this success and that of the subsequent book, the authors describe it in the Preface to the third edition of the book in 1884, perhaps tongue-in-cheek, as “atrocious”, noting that “it contains a little of everything that a novelist ought not to include, and almost everything that a critic would wish to see removed”. The text was heavily reworked by Eça de Queirós prior to publication of the third edition, such that he was the lead author for the book version, whereas Ortigão's name had come first at the end of the serialization.
