midnight
In supposing himself supplanted by a rival , he found the key to what seemed inexplicable in Mariette 's letter and in her conduct . He therefore tenaciously clung to the belief of her infidelity , longing for the moment when he might demand an explanation from this audacious commander . He now abandoned his first resolution of seeing Mariette , and retraced his steps homeward in a state of deep agitation and painful excitement . It was midnight when he again entered their dreary room . His father was anxiously waiting for him ; but one glance at his son 's gloomy countenance reassured the old man . Feeling certain that the lovers had not met and that his stratagem was still undiscovered , he again proposed a visit to Dreux on the following day ; but Louis threw himself dejectedly on his bed , declaring he must have time for reflection before taking such a grave step . After a night of sleepless agony , the young man rose at dawn and quietly slipped out of the room , glad to escape his father 's questioning for a few hours .