You know where Gide is going with this book because he warns you in his preface that there is going to be some odd behaviour from the lead character. Things start reasonably quickly with Michel becoming ill almost as soon as his honeymoon starts. He manages to get over to Tunisia after sailing from the South of France but starts coughing up blood and is soon consigned to bed with the diagnosis of tuberculosis.
His wife, who he actually starts to fall in love with after it having been a business type of relationship up until that point, nurses him and does all she can. But it is Michel himself who decides to try to take his health into his own hands and before too long he has started to improve and is taking walks without her. He seems annoyed at her mothering now he can walk around.
Just as his health returns there starts to be a shift in his mental outlook and you sense that having touched death he is now going to live life in a slightly different way.