We are asked to believe that the central character, Jean Perdu, lived in seclusion for 21 years, as he believed his lover had abandoned him. An unread letter reveals a different story, and so he sets out in pursuit of the truth, accompanied by some other less than credible characters on their own quests.
The best writing comes from the author's lyrical descriptions of French countryside.
Sadly, this isn't enough to save a novel too heavily reliant on co-incidences and an insubstantial plot.