* D'Artagnan's growth throughout the series, which sees him just ''about'' able to take on two musketeers in the first episode...to taking on a beast like Lafarge and becoming a Musketeer due to his valour.
* In the first season finale, the Musketeers engineering an accidental public confession for the Cardinal, in which he implicates himself in the assassination attempt on the Queen.
** Topped only by the Musketeers being BigDamnHeroes and going to rescue Constance, held hostage by Milady. It's the four of them versus a gang of season thieves and killers, and the bad guys ''do not stand a chance.'' You know it's awesome when the theme song is blaring throughout the sequence.
* Constance taking out an armed baddie with a sword. She's only been taking lessons for a short time, she's holding the sword with ''both hands'' so she doesn't drop it, and yet she stabs him, disarms him, and smacks him over the head while Aramis sits behind her [[ItMakesSenseInContext with his hands full.]]
* In 2.02, D'Artagnan and King Louis have been captured by a gang to be sold to Spain as galley slaves. The man responsible has no idea who Louis is, and finally demands the truth, otherwise he will shoot D'Artagnan. Cue Louis calmly standing up tall and staring the criminal down.
-->'''King Louis:''' I am Louis, son of Henry IV of the House of Bourbon and Marie de Medici. I am your king, and ''you cannot treat me this way!'' *punches Sebastian in the face*
** And from the same episode, we have a villainous one for Milady de Winter. She goes from being Sebastian's lover/accomplice (which is several steps down from when she was working for Cardinal Richelieu) to gaining the King's favour (and lust) by saving his life and playing the victim.
** D'Artagnan calmly and implacably facing off against Gus (the boss of the whole operation) alone with Gus ''charging'' him down with his sword drawn on ''horseback'' and D'Artagnan, on foot, "armed" only with Athos' borrowed scarf. The youngest Musketeer then uses said scarf to grab said sword, throw the rider to the ground and stab the sonuvabitch when he's down.
* Constance sneaking the deathly ill Dauphin out of the palace at night so she can let him sleep in a public laundry place, to let the steam clear his lungs so his fever can break. She nearly gets executed when she and the baby are found, but fortunately the cure works and the Dauphin's life is saved thanks to her quick thinking.
** Spanish general Alamand pulling a TakingYouWithMe on his racist former lieutenant, killing them both and destroying the formula for the white gunpowder forever.
* A villainous one for Rochefort in 2.04. He finds out who Milady is and pays her to assassinate the Spanish ambassador who's been conspiring with him (and who is on the verge of telling the King everything) while under the Musketeers' protection. This costs Treville his job as Captain, this removing the only other person in King Louis' inner circle that can still influence him.
* Treville in 2.05, showing everyone how he earned the title of Captain even though he's no longer in command, by convincing the villagers of Pinon to fight for their land, training them into a semi-acceptable militia and giving them orders during the siege.
* Milady escapes Marmion in 2.06, and immediately rides to the Musketeer garrison to warn them that the King is being held hostage. And then she personally helps in the mission, sneaking back into the chateau and dispatching a few baddies herself. Her reward for all this is to be summarily dismissed by Louis because she 'abandoned' him and was dressed like a man.
** From the same episode, Constance is about to be shot by Marmion. Very calmly, she tells him to look her in the eye when he shoots her, and to think about how ''ashamed'' his family would be if they could see the kind of monster he's become in his quest for revenge. Even Marmion's brother agrees with her, telling him he's gone too far.
** Aramis surviving a fall from a glass window, and ''climbs back up'' to rescue the Queen and the Dauphin. All while bleeding and having an injured leg.
** Rochefort reminding everyone that he used to be a soldier before he became the King's minister, dispatching Marmion's thugs before gunning down the man himself. It's also a CallBack to the beginning of the episode, where Rochefort told Marmion that he would kill him himself.
* The Musketeers refusing to bow to Rochefort after the King makes him First Minister.
* Constance ''immediately'' coming to the Queen's defense when she sees Rochefort trying to rape her.
** Topped by Queen Anne taking her hairpin out while Rochefort is distracted and stabbing the sonuvabitch right in the eye. However, it doesn't stop Rochefort from immediately running to the King to tell him of Anne's infidelity with Aramis.
* Porthos wiping the floor with his racist and vile half-sister's equally racist and vile husband in a duel after the man spat on him. Aramis has to step in and tell Porthos that he's made his point.
** Athos, Aramis and D'Artagnan freeing the village girls who were kidnapped by the couple to be sold to men for their 'purity.'
* Constance choosing to stay in the palace to watch over the Dauphin while the Queen escapes from Rochefort's wrath, knowing full well that she will be caught up in Rochefort's machinations and punished in the Queen's place.
* The Musketeers unanimously coming to the Queen's defense despite Rochefort's accusations against her.
* The season two finale, including:
** Porthos taking on the Spanish spymaster Vargas and his men, using the French countryside to his advantage and managing to take down a number of them until the other Musketeers arrive.
** The beginning of the episode, where the Musketeers save Constance from her execution right in the middle of the palace.
** Rochefort goes to Aramis and says the Queen and her son will be exiled instead of executed, if Aramis will give a full confession to the affair. Aramis decides to use his moment in court to publicly denounce Rochefort for assaulting the Queen and being a lying ManipulativeBastard.
** Then at the climax of the episode, the Musketeers storm the Palace and deliver Vargas to the King so he can finally know the truth of Rochefort. Meanwhile, Aramis and Constance rescue Queen Anne from being murdered by Rochefort and fight him off until he's finally finished by D'Artagnan.
** Treville being appointed as Minister of War. He uses his new position to name Athos the new Captain of the Musketeers.
* Season three starts with the Musketeers leading a charge right through Spanish infantry and taking out their cannons in less than five minutes.
** Aramis shows that four years in a monastery is not enough time for a Musketeer to forget his training, as he lays waste to a group of hired thugs who threaten the children under his care.
** Constance takes her role as caretaker of the cadet Musketeers ''very'' seriously. When one of them gets beaten up for sport by the Red Guard captain, she burns all their uniforms as they bathe so they have no choice but to run through Paris naked. Treville himself gets in on it, confronting the captain and telling him to 'pick on someone [his] own size' before knocking him out with one punch.
* 3.03, in which the Musketeers and Treville end up fighting against the Red Guard in an escalating situation involving the King's younger brother and the theft of some incriminating documents. Outgunned and outmanned, the Musketeers decide to make one last charge...only for [[TheCavalry Constance and the cadets to come running in, swords drawn.]] And to top it off, Sylvie comes rushing in, heading the other retired Musketeers. The Red Guard gets quickly overwhelmed, and their Captain Marcheaux gets punched in the face by Treville.
* Treville effortlessly running rings around Gaston and the Duke of Lorraine - promising each of them what they want, destroying their alliance & getting the Duke to pull back his army and sign a treaty - all in the space of one afternoon.