After his uncle’s Charles Darnay marries Lucy Manette and continues to work as a tutor. This is significant because he is now the heir to the title Marquis St. Evremonde.
Darnay renounced his family name when he left for England, but he still cared about his uncle. Darnay returns to visit his uncle, the Marquis St. Evremonde, and questions his family’s perpetual mistreatment and exploitation of the poor. His uncle refuses to change his ways, believing he is entitled to his privileged position. Very soon after Darnay leaves, the marquis is stabbed to death.
Unable to change his uncle’s ways, Darnay accepts the fact that you cannot choose your family and tells Dr. Manette his real name (causing him to have another shoe-making relapse). He marries Lucy, and settles into domestic contentment. However even though he renounced the title, he is still the new Marquis St. Evremonde and is marked for death by Madame Defarge and the revolutionaries.