Planchet brings d'Artagnan two letters, a small one in a simple envelope and a large, imposing one with the cardinal's coat-of-arms on it. The small letter, although unsigned, is from Constance Bonacieux, instructing him to be on a certain road at 7 p.m. The other letter instructs d'Artagnan to be at the cardinal's palace at 8 p.m. D'Artagnan arranges for his three friends to be posted outside the cardinal's house, and then he purchases one of Aramis's elegant horses that was "mysteriously" sent to him by an unknown benefactoress and rides out to keep the seven o'clock appointment with Constance Bonacieux. Fleetingly, Constance appears at the window of a heavily guarded carriage; she throws him a kiss and gives him a sign not to acknowledge her.
D'Artagnan then returns in time for his eight o'clock appointment with the cardinal. At the beginning of the interview, the cardinal demonstrates that he knows many things about d'Artagnan — for example, he knows about d'Artagnan's first encounter with "the man from Meung," his losing the letter of introduction to Treville, his trip to England, his meeting with the duke of Buckingham, and his meeting with the queen and her gift of the diamond ring. The cardinal assures d'Artagnan that he respects him highly, and he then offers him a position as lieutenant in his own guards — a very distinguished post. He also lets d'Artagnan know that he is aware of d'Artagnan's nocturnal activities, and he suggests that d'Artagnan needs protection from ladies who love him. He cautions d'Artagnan that if he were in the cardinal's service, he would have that protection. D'Artagnan refuses the offer because all of his friends are musketeers; he feels that he couldn't fit in with members of the cardinal's guards. The cardinal warns d'Artagnan that if something unfortunate should happen to him, it won't be the cardinal's fault. However, the cardinal does promise d'Artagnan that, for the time being, his feelings toward him are neutral; he is waiting to see how d'Artagnan conducts himself during the siege of La Rochelle.
Next day, during the inspection of the troops, all of the musketeers are magnificent in their new trappings. In fact, d'Artagnan is so concerned with his own appearance that he does not see Milady pointing him out to some sinister-looking, low-class rogues.
In Chapter 39, d'Artagnan believes that Constance Bonacieux is still in captivity because she will not acknowledge him and his actions; later, however, we discover that she is being secretly transported according to the instructions of the queen to a rural convent for her protection.
Chapter 40 gives us one of the few favorable views of the cardinal. This is also the scene of the long-awaited meeting between d'Artagnan and the cardinal, and we are anxious to see how d'Artagnan conducts himself during the confrontation, Historically, Cardinal Richelieu was a superb diplomat, one of the most powerful men of his era; today, his name is far more famous than that of his king, Louis XIII.
In this scene, we see that the cardinal is fair; he respects virtue and loyalty, and he acknowledges d'Artagnan's superior qualities by offering him a promotion in the guards. Earlier, this offer would have been an undreamed-of opportunity for a young man from Gascony, but now d'Artagnan has formed his own allegiances. He refuses the cardinal's offer with a subtle and effectively diplomatic answer, proof that he has learned a great deal during his short stay in Paris. The cardinal's promise to be neutral, that he won't personally persecute or hound d'Artagnan, gives us a fuller perspective of Cardinal Richelieu. We are being prepared for d'Artagnan's ultimate alignment with the cardinal at the end of the novel.