Plot
The young d'Artagnan witnesses the murder of his parents at the hands of Febre, a cruel swordsman in the employ of Cardinal Richelieu. D'Artagnan is nearly killed after using his dead father's sword to attack Febre, who is then left with a permanent scar and the loss of his left eye. The wounded boy is taken in by Planchet, a family friend and former member of the Musketeers, the loyal protectors of Louis XIII.
Fourteen years later, the adult d'Artagnan finds on his arrival in Paris that the musketeers have been disbanded by order of Richelieu, who plots to usurp the king's authority and render him a powerless figurehead. Richelieu is also trying to foment hostility between France, England, and Spain to gain more political power for himself. D'Artagnan convinces two veteran musketeers, Porthos and Aramis, to free the imprisoned head of the musketeers, Captain de Tréville, thus earning their trust.
He takes a room at a Paris boarding house, where he takes a fancy to the chambermaid, Francesca, who is the daughter of the late seamstress to the queen. Febre, on orders from Richelieu, incites a mob to attack the royal palace during a state dinner for Lord Buckingham, a visiting English dignitary. D'Artagnan, with the help of Porthos, Aramis and another musketeer, Athos, saves King Louis, the queen, and Lord Buckingham from being hurt or killed. Afterwards, Francesca recruits d'Artagnan to make a clandestine trip to the north coast of France with the queen to meet with Buckingham in an effort to keep peace between the two countries. However, d'Artagnan's landlord overhears them and tells Febre.
During the trip, d'Artagnan fights off repeated attacks by Febre's henchmen. He and Francesca become intimate, only to have Febre discover them and kidnap her and the queen. Febre forces the queen to write a letter to Buckingham asking him to meet her at a heavily fortified castle of his choosing, using the queen's ring to convince him of the authenticity of the message. Richelieu realizes that the jingoistic Febre intends to incite full-blown war between England and France. Knowing that he has lost control of his chief henchman, his bodyguard, Rochefort, attempts to stop Febre, but is easily cut down and killed. Determined to stop Febre, Richelieu secretly visits d'Artagnan and tells him of Febre's plans and pleads for his help to stop Febre. D'Artagnan agrees, but only because Febre is holding Francesca. D'Artagnan soon learns that his landlord sold him and Francesca out and promises him to kill him should he fail to save Francesca.
D'Artagnan returns to Paris and convinces the surviving musketeers that their responsibility to the crown remains their highest priority, and they join him at the castle where Francesca, the queen, and Lord Buckingham are being held. They charge the castle on horseback, losing several of their number in the process, but the diversion they create allows Planchet to drive his carriage in front of the castle gates below the field of enemy cannon fire. This enables him to fire a concealed mortar and create an opening.
The remaining musketeers easily deal with Febre's men, while d'Artagnan engages Febre himself in an intense duel, finally killing him and avenging the death of his parents. D'Artagnan and the three surviving musketeers are given medals for their service, and d'Artagnan covertly threatens Richelieu. At the end, d'Artagnan and Francesca are seen to be married.