Darnay makes the decision to return after receiving a letter from his former servant begging for help. Darnay used to be a marquis and owned a considerable tract of land that was looked after by Monsieur Gabelle. After Darnay renounced his title, he left Gabelle in the position of watching the Darnay land, which untimately resulted in Gabelle's arrest for siding with the aristocracy. Darnay feels that he should have tied up the loose ends of his actions in a way that wouldn't have left people vulnerable. Darnay is torn and does not want to return and put himself at risk, but he feels that it's necessary in order to clear his conscience. Gabelle's only crime was being loyal to Darnay even when Darnay himself was hardly being loyal to himself—relinquishing his title, running away, and leaving Gabelle to pick up the pieces. This shows that he has decency and dedication to his old servant.