By the time Athos and Raoul reach Toulon, there is no sign of D’Artagnan, and his trail has since gone cold. One fisherman at the docks says they cannot take to the water yet, since he needs to repair his boat due to a nobleman loading a hefty carriage case onto the vessel and insisting on a speedy voyage. The fisherman tried protesting, but the man beat him with his cane. When he tried to involve his guild, the man presented papers that overrode their authority, leaving the fisherman no right to refuse. While on the water, the fisherman tried to protest again when the man wanted to change his route, and the man attacked him. The fisherman took out his ax in self-defense but was caught off-guard when a second man emerged from the carriage case. This second man wore “a black helmet and a black mask,” which covered his entire face and head (260). The fisherman jumped overboard, fearing the second man to be a devil, and the boat drifted into the sands of Ste. Marguerite’s. The two men left unscathed, and the fisherman recovered his boat after they both left.

Athos and Raoul journey onward to the island where the boat ran aground, hoping to see the governor of Ste. Marguerite’s and investigate the fisherman’s claims. Once ashore, Athos and Raoul find a fortress tucked away among the fruit trees, patrolled by a single soldier. Athos suddenly sees a hand waving at them from a high window. The hand throws down a silver plate, onto which a message was carved with a knife. The carving reads: “I am the brother of the King of France—a prisoner today—a madman tomorrow. French gentlemen and Christians, pray to God for the soul and the reason of the son of your masters” (262). Suddenly, a soldier on the wall fires his musket at them. They narrowly avoid being shot as the soldier tells his comrades to make ready another round of fire. More soldiers move from the garrison to prepare their muskets when D’Artagnan suddenly runs up behind Athos and Raoul, ordering the soldiers to hold their fire. D’Artagnan explains that they were fired upon because they read the message on the silver plate; he tells the fortress governor that Athos and Raoul are Spaniards and cannot read French, and he then scratches out the words on the plate, saving all three of their lives.

D’Artagnan, Athos, and Raoul share with one another the information they know about the prisoner and, by sharing all their knowledge, they arrive at the same conclusions: the prisoner is a secret prince of France, and Aramis is now a fugitive for his involvement in the scheme. D’Artagnan worries about Athos and Raoul’s safety since they know Philippe’s identity. Later, D’Artagnan and Raoul discuss the young man’s love for La Valliere. D’Artagnan suggests he visit her one last time because seeing her with a jealous man's eyes might make him fall out of love. Raoul does not think this would be possible, and D’Artagnan suggests that he instead write her a letter before he leaves for Africa. At first, Raoul writes a long letter declaring his continuing love for her, but D’Artagnan suggests something more straightforward. Raoul writes a letter stating that he wants to tell her he loves her one more time, and then to punish himself for writing it to her, he would go to Africa and die. He asks D’Artagnan to deliver the letter to La Valliere on the occasion of his death. Outside, a boat arrives.

The boat carries a messenger from King Louis, bearing an order for D’Artagnan to return to Paris immediately. D’Artagnan offers Athos a ride back with him, but Athos insists on staying with Raoul until he leaves for Africa. Athos says he will arrive in Paris no more than a few days after D’Artagnan. Athos and Raoul finish preparations for De Beaufort’s departure. De Beaufort himself arrives in due time, and after inspecting Raoul’s work, he praises his diligence and invites Athos and Raoul to dine with him that night. As it is the evening before they set sail, Athos and Raoul decide to decline the invitation, preferring to share one more meal together before parting. Father and son share an emotional goodbye, and Athos decides to send Grimaud, their aide, along with Raoul so he will not be without a friend in Africa. Raoul and Grimaud board the admiral’s vessel, and Athos returns to his camp alone.