The brightest and best musketeers of the King's Regiment - Athos, Porthos and Aramis - are dispatched by Captain Treville to find a missing musketeer carrying important letters on behalf of King Louis. Meanwhile, d'Artagnan travels from his family farm in Gascony to Paris to petition the king, but his peaceful plans are turned upside down.

Vadim is determined to make life as unbearable as possible for the authorities that have imprisoned him, after he manages to organize a full-scale riot.

The Duke of Savoy and his wife, the king's sister, arrive in Paris at the same time as Marsac, a former Musketeer, now a deserter, who seeks Aramis's help after an abortive attempt on the duke's life. Marsac's troops were massacred as they slept whilst on a mission to depose the Duke. Marsac's informant tells him they were betrayed to the Duke by Captain Treville, the leader of the Musketeers. Aramis discovers that all records of the night of the massacre have disappeared, whilst the duke suspects that Richelieu was behind it and has located a Spanish spy who can prove it. The Musketeers must prevent the Duke from starting a war with France, as well as proving their captain's innocence.

King Louis's treacherous mother, the exiled Marie de' Medici, returns to seek protection from an assassin. Aramis and d'Artagnan sent to collect a young woman, Agnès, and her baby son are stunned when armed men abduct the baby and the Musketeers seek to find the baby and uncover who they were sent to escort.

The musketeers must save an enlightened woman who has been accused of witchcraft.

Frustrated by his wife's infertility, Louis makes a foolish statement, suggesting it were best if she were dead. As a result, Richelieu sends Irish gunman Gallagher and his gang to kill her while she is travelling with the Musketeers. Sending their friends back for reinforcements, Aramis and Athos take her to a convent for sanctuary, where Aramis is surprised to see his former love, Helene is one of the nuns, though she and the Mother Superior prove themselves very capable in the subsequent siege. However, it is with the queen that Aramis grows intimate, to Athos's horror. The siege is lifted, the queen saved and the king contrite whilst Richelieu manages to frame somebody else for the assassination attempt.

Milady seeks her revenge against the Musketeers. Will the Musketeers outwit her or will she destroy them by manipulating their weakest link; D'Artagnan?

The Musketeers return and must rescue a French general from an impenetrable Spanish prison.

D'Artagnan must protect king Louis when a notorious criminal kidnaps them both.

Moroccan Tariq Alaman approaches the court with the offer of the formula for a super-strong explosive if the musketeers will help him rescue his daughter Samara from Spanish agents who want the formula themselves. The rescue attempt is bungled with several innocent bystanders being killed and the wounded Porthos also taken captive. Under cover of seeming to deliver Tariq to the Spaniards the musketeers attempt a second rescue bid with mixed results. Meanwhile the dauphin is ill and both Milady and Rochefort attempt to exploit the situation but it is Constance who takes matters into her own hands to save the baby's life.

A peasant girl, who believes she is spoken to by God, raises a French movement against Spain.

The king is taken hostage by an astronomer and is forced to make an impossible choice.

On her way to marry the crown prince of Sweden, Princess Louise of Mantua, the king's cousin, is attacked by would-be kidnappers who are killed by the musketeers. The attackers were paid in Spanish gold but Rochefort has had a hand in the operation. Louise is brought to Paris for her own safety but another attempt is made on her life and the musketeers link the weaponry used to Rochefort. Ultimately they are more concerned with the princess herself, who may not be what she seems, whilst Rochefort is suspicious of Aramis's relationship with the queen and Constance's husband is a casualty in a shoot out.

Porthos uncovers the truth about his past and questions his allegiance to the musketeers

After the queen is accused of treason, the Musketeers put their lives on the line in order to get her to safety and prove that Rochefort is a Spanish spy.

The Musketeers risk all to save France from Rochefort's treachery; Porthos works to lure the Spanish spy-master to Paris; Athos and d'Artagnan attempt to rescue Constance.

Athos, Porthos and d'Artagnan have been at war, while Aramis has been at the monastery caring for the children left orphaned. Missing munitions brings the three to the monastery where the bad guys have taken refuge. As they scheme to stop the stolen munitions from being sold to the Spanish and save the Monks and the children, Aramis is forced back into battle and has to decide where he truly belongs.

Refugees from the war are targeted by Feron for stealing grain in a plot to force the King to pay a higher price to feed the citizens of Paris. The Musketeers must work with one of them, Sylvie, to prove their innocence.

King Louis orders the Musketeers to bring his exiled brother, the Duke of Orléans, back to Paris. On the way, the Duke gets robbed of dangerous letters which could destroy Orléans. The Duke informs the corrupt Governor of this, and the Governor's Red Guard must race the Musketeers in the hunt for the thief.

On her journey to Paris the queen of England, Henrietta Maria, also the sister of King Louis is robbed of the crown jewels, which has to be sold in order to finance England's armed forces. The Musketeers quickly discover the thief to be Émile Bonnaire, a flamboyant but pathetic criminal they encountered previously. Athos, Porthos and D'Artagnan pressure Bonnaire into leading them to the diamonds' buyers to recover them. Aramis on the other hand, reconnects with Pauline, a childhood friend he grew up with in a bordel where their mothers lived and worked. She is set to marry a French nobleman but is being blackmailed by someone threatening to reveal the circumstances of her childhood, and Aramis tries to resolve the situation peacefully.

A riot is taking place at the prison, the king has his hands full with his son's birthday.

Feron forges a letter supposedly from Treville sending the four musketeers on an errand, intending that they will be murdered on the way but before they set out Athos survives an attempt on his life by Grimaud, who also springs Gaston from jail, whilst the king asks Aramis to accompany him on a pilgrimage to his father's grave. On their own Porthos and D'artagnan must weather an attack until their comrades rescue them after which the normally obtuse king, having realized the Dauphin's parentage, nonetheless joins with Aramis and the other musketeers to defeat his would-be killers, including Feron. However Grimaud escapes with Gaston, whom he intends to crown king as he believes Louis to be terminally ill.

The musketeers pursue Grimaud and find themselves in a forest community peopled by women, led by the fearsome Juliette, who have also taken in the wounded Bastien, whom the musketeers identify as an army deserter. When other, disaffected ex-soldiers lay siege to the village the musketeers defeat them, learning what their attackers were seeking whilst Athos discovers a link between one of the women and Grimaud. In Paris, following Feron's death, the king and queen get closer.

With the king taking to his bed as dying the queen asks Aramis to help broker a peace treaty with her brother, the Spanish king and he sets out to meet the ambassador but is captured by Grimaud. The court then receives an ultimatum - the return of Aramis in exchange for captured Spanish soldiers, a ploy engineered by Grimaud, Gaston and the Duke of Lorraine to discredit the queen as an appeaser. Facing popular acrimony the other musketeers have the prisoners released and set out for the rendezvous, along with D'Artagnan's cousin Espoir, whom he has saved from the gallows and acquits himself well in the gun-battle. Aramis is freed but Grimaud escapes to use the queen's sponsorship of a literacy scheme for the poor against her and Athos's new love Sylvie whilst an old enemy of the musketeers returns to the court.

Treville takes controversial steps to protect the Dauphin as France's enemies draw closer. Will his secretive tactics drive the musketeers apart?

Following Treville's funeral the musketeers survive an attempt by Grimaud to kill them when their garrison is torched, leaving many casualties, and gunpowder and weapons stolen. To lure the musketeers into a trap Grimaud takes hostages including Sylvie but the four comrades stage a rescue, and the queen and Dauphin are restored to the palace with Milady as the royal spy master, her first task being to take care of Gaston. However the mortally wounded Grimaud escapes and the musketeers must stop him from blowing up the city with the stolen gunpowder.

Porthos uncovers the truth about his past and questions his allegiance to the musketeers

A peasant girl, who believes she is spoken to by God, raises a French movement against Spain.

Frustrated by his wife's infertility, Louis makes a foolish statement, suggesting it were best if she were dead. As a result, Richelieu sends Irish gunman Gallagher and his gang to kill her while she is travelling with the Musketeers. Sending their friends back for reinforcements, Aramis and Athos take her to a convent for sanctuary, where Aramis is surprised to see his former love, Helene is one of the nuns, though she and the Mother Superior prove themselves very capable in the subsequent siege. However, it is with the queen that Aramis grows intimate, to Athos's horror. The siege is lifted, the queen saved and the king contrite whilst Richelieu manages to frame somebody else for the assassination attempt.

With the king taking to his bed as dying the queen asks Aramis to help broker a peace treaty with her brother, the Spanish king and he sets out to meet the ambassador but is captured by Grimaud. The court then receives an ultimatum - the return of Aramis in exchange for captured Spanish soldiers, a ploy engineered by Grimaud, Gaston and the Duke of Lorraine to discredit the queen as an appeaser. Facing popular acrimony the other musketeers have the prisoners released and set out for the rendezvous, along with D'Artagnan's cousin Espoir, whom he has saved from the gallows and acquits himself well in the gun-battle. Aramis is freed but Grimaud escapes to use the queen's sponsorship of a literacy scheme for the poor against her and Athos's new love Sylvie whilst an old enemy of the musketeers returns to the court.

A riot is taking place at the prison, the king has his hands full with his son's birthday.

After the queen is accused of treason, the Musketeers put their lives on the line in order to get her to safety and prove that Rochefort is a Spanish spy.

Following Treville's funeral the musketeers survive an attempt by Grimaud to kill them when their garrison is torched, leaving many casualties, and gunpowder and weapons stolen. To lure the musketeers into a trap Grimaud takes hostages including Sylvie but the four comrades stage a rescue, and the queen and Dauphin are restored to the palace with Milady as the royal spy master, her first task being to take care of Gaston. However the mortally wounded Grimaud escapes and the musketeers must stop him from blowing up the city with the stolen gunpowder.

The musketeers pursue Grimaud and find themselves in a forest community peopled by women, led by the fearsome Juliette, who have also taken in the wounded Bastien, whom the musketeers identify as an army deserter. When other, disaffected ex-soldiers lay siege to the village the musketeers defeat them, learning what their attackers were seeking whilst Athos discovers a link between one of the women and Grimaud. In Paris, following Feron's death, the king and queen get closer.

King Louis orders the Musketeers to bring his exiled brother, the Duke of Orléans, back to Paris. On the way, the Duke gets robbed of dangerous letters which could destroy Orléans. The Duke informs the corrupt Governor of this, and the Governor's Red Guard must race the Musketeers in the hunt for the thief.

Milady seeks her revenge against the Musketeers. Will the Musketeers outwit her or will she destroy them by manipulating their weakest link; D'Artagnan?