The young D'Artagnan wants to be a musketeer and for this he travels the long way to the city of Paris in France, where he will enter the same academy for musketeers that his father had attended. On his way to Paris, however, he meets up with Monsieur Rochefort. D'Artagnan does not know that his rivalry with Monsieur Rochefort will get him involved in a battle against the evil plot thought up by Cardinal Richelieu against the king and queen of France. When Cardinal Richelieu discovers that the queen had sent valuable diamonds to the Duke of Buckingham in England, a country enemy of France, the cardinal uses the information to blackmail the queen and create a difficult situation between her and King Louis, who now believes his wife to be in love with the Duke of Buckingham. Nobody knows that the diamonds are in possession of an old woman, Milady, who had stolen the diamonds from the duke and had brought them for Rochefort so that they would be nowhere to be found; Rochefort allows her to hold on to the diamonds in order to ensure this.
Shortly after entering the academy of musketeers, D'Artagnan meets three of the finest among them, Porthos, Athos and Aramis. Though their first meeting had not gone well and had led to the challenging of several duels, the four of them become fine friends shortly after, since all four fight against the Cardinal's soldiers. When searching for lodging in Paris, D'Artagnan meets the lovely Constance Bonacieux, a good friend of the queen. Cardinal Richelieu orders all of the queen's closest friends to be arrested so that no one will be able to defend her once King Louis decides to have her beheaded. D'Artagnan defends Constance when a group of soldiers try to insolently have her arrested and then takes her to the safety of the queen. Constance trusts the queen and when she learns of the awful accusation that's been laid upon her, the woman asks of D'Artagnan to travel to England and fetch the Duke of Buckingham, the only one who may now save the queen. D'Artagnan, now in love with Constance but not fully trusting of the queen, gathers his three friends, the three musketeers and all of them travel to England together. There, they meet the Duke of Buckingham, as well as Milady, who confesses the crime of theft she is committed and attempts to murder the duke, believing he is in love with the queen of France instead of her. The five of them, D'Artagnan, the duke and the three musketeers, return to France just as the queen is being led to the guillotine. King Louis begs his wife to lie to him, to tell him that she did not send the diamonds out for the Duke of Buckingham, even if she did, but the queen refuses.
When the cardinal and the soldiers discover the presence of the duke, they fear for the safety of the king and attack the five men. As D'Artagnan comes close to finishing off Rochefort, the Cardinal calls everyone to stop, for the King himself does not wish Rochefort to be harmed. The Duke of Buckingham then bows before King Louis and explains to him that he is in reality the brother of his wife, not the lover. The queen explains that she and her brother had been separated and that she had been sent to France. She had sent the diamonds to the Duke to prevent him from being locked up when he was left almost penniless and when difficulties had begun between France and England. She had had to remain silent, for she could not reveal she was sister to the duke of a land enemy to her own. King Louie then apologizes to his wife for doubting her, befriends the Duke of Buckingham, declares peace between their two countries and finally declares D'Artagnian as an official musketeer in his service.
Who is killed D'Artagnan or Rochefort?
Neither Rochefort