However, en-route, at an inn in Meung-sur-Loire, d'Artagnan overhears an older man making jokes about his horse and, feeling insulted, demands to fight a duel with him. The older man's companions beat d'Artagnan unconscious with sticks andbreak his sword; his Letter of introduction to Monsieur de Tréville, the commander of the Musketeers, is stolen. D'Artagnan resolves to avenge himself upon the man, who is later revealed to be the Comte de Rochefort, an agent of Cardinal Richelieu, who is in Meung to pass orders from the Cardinal to Milady de Winter, another of his agents.
In Paris, d'Artagnan visits de Tréville at theheadquarters of the Musketeers, but the meeting is overshadowed by the loss of his letter and de Tréville refuses his application to join. From de Tréville's window, d'Artagnan sees Rochefort passing in the street below and rushes out of the building to confront him, but in doing so he separately causes offense to three of the Musketeers, Athos, Porthos, and Aramis, who each demand satisfaction; D'Artagnanmust duel each of them in turn that afternoon.
When d'Artagnan prepares himself for the first of the three duels, he realises that his counterparts are friends. But just as he and Athos begin to fight, a number of Cardinal Richelieu's guards appear; they try to arrest the three musketeers and d'Artagnan for illegal dueling. Although outnumbered, the four men win the ensuing battle. In thecourse of events, d'Artagnan duels and seriously wounds Jussac, one of the Cardinal's officers and a renowned fighter. After hearing about this event, King Louis XIII appoints d'Artagnan to des Essarts' company of guards and gives him 40 pistoles (currency).
D'Artagnan hires a servant, Planchet, finds lodgings, and, by decree of the King, joins Monsieur des Essart's company of Guards, a lessprestigious regiment in which he must serve for two years before being considered for the Musketeers. Shortly after his landlord comes to see him to talk about his wife's kidnapping (she is released presently), he falls in love at first sight with his landlord's pretty young wife, Constance Bonacieux. She works for the Queen Consort of France, Anne of Austria, who is secretly conducting an affair withthe Duke of Buckingham. The Queen has just received a gift from her husband Louis XIII and trying to console her lover she gives him the diamonds as a keepsake. Cardinal Richelieu, who tries to start a war between France and England, wants to reveal that. Quickly he organises an event and talks the King into demanding that his wife wear the diamonds at this opportunity.
Constance doesn'tsucceed in sending her cowardly husband, who has been manipulated by Richelieu, to London, but d'Artagnan and his friends decide to help. On their mission they are frequently attacked by the cardinal's henchmen and therefore only d'Artagnan and Planchet arrive in London (although Planchet does not accompany d'Artagnan to see Buckingham). In the process of getting to England, d'Artagnan is compelled toassault and nearly kill the Comte de Wardes, a friend of the Cardinal's, cousin to de Rochefort, and Milady's lover. Although two of the diamonds have been stolen by Milady, the Duke of Buckingham is able to provide replacements while delaying the thief's return to Paris. D'Artagnan is thus able to return a complete set of jewels to Queen Anne just in time to save her façade of honour and receivesfrom her a beautiful ring as an expression of her gratitude.
Shortly afterwards, d'Artagnan attends a tryst with Madame Bonacieux, but she does not open her door. He notices signs of a struggle, and, asking about, discovers that de Rochefort and Monsieur Bonacieux, acting under the orders of the Cardinal, have assaulted and imprisoned her.
D'Artagnan looks after his friends, who have...