When Darnay returns to Paris in a bid to save Gabelle, the faithful old family servant imprisoned by the revolutionaries, he is immediately caught up in the continuing revolutionary turmoil there, the class conflict that threatens to engulf the entire city. The revolutionary fervour is gathering apace, with a raft of increasingly harsh decrees being passed against aristocrats and emigrants. Darnay, who happens to be both, is especially at risk. He had optimistically and naively believed that he could perhaps return safely to the city as he has renounced his aristocratic name and property, but this avails him nothing. He does take time to reflect on the wisdom of such a course before setting out, but on the whole he seems to suffer relatively few misgivings as to the wisdom of his actions in returning to the strife-filled city; it is the external social conflict, not an inner one, that he principally has to contend with.
At first Darnay finds it difficult even to travel in France; his every movement is closely watched. His arrest and imprisonment swiftly follows, and although he appeals to Defarge, Defarge staunchly declares himself to be on the side of France and the French people against people like Darnay, who is now deemed an out-and-out traitor by the revolutionaries. The very fact of Darnay’s aristocratic background is quite enough to condemn him. He now realizes his own folly at having returned to his native land:
That he had fallen among far greater dangers than those which had developed themselves when he left England, he of course knew now. That perils had thickened about him fast, and might thicken faster and faster yet, he of course knew now. He could not but admit to himself that he might not have made this journey, if he could have foreseen the events of a few days. (Book III, chapter 1)
However, his return to Paris was of course based on the most honourable principles – the desire to save someone’s life – and in this light his actions are seen are commendable. He has put himself in the way of danger for someone else's sake. Furthermore, the worst excesses of the Revolution are yet to come, and it is intimated that someone as ‘gentle’, courteous, and kindly as himself cannot even imagine such horrors as those that the Reign of Terror will presently unleash. Indeed, at this stage the perpetrators themselves are presented as being unaware of their future grisly actions, when they will come to execute so many of their fellow country-men:
The frightful deeds that were to be soon done, were probably unimagined at that time in the brains of the doers.
There is a strong sense here that the revolution is creating its own terrifying momentum, inexorably sweeping along the peaceful-minded and the bloodthirsty, the innocent and the guilty alike in its grim wake.