The Fifth Doctor and Peri plan to drop off new companion Princess Erimem at the Braxiatel Collection (home of Bernice Summerfield), but land in 17th century France instead, where skirmishes between King Louis XIII's musketeers and Cardinal Richelieu's guards are threatening the peace in Paris. Also, Peri immediately gets kidnapped by the English Duke of Buckingham, because everyone mistakes her for Queen Anne. As it turns out, Buckingham plans to invade France and start the British Empire a couple of centuries early.
Fortunately for the Doctor, this is actual realistic France, where Cardinal Richelieu is just a pretty okay guy and the Only Sane Employee. Even more fortunately, Erimem is extremely adept at exactly this kind of scenario, and bluffs her way into the court, holds a Rousing Speech to inspire the army, and even joins in the battle with her excellent sword fighting skills.
The Doctor decides that Erimem can stay and become a proper companion, although he's not thrilled to have her pet cat Antranak along.
"No Place Like Home" takes place immediately after this.
- Accidental Kidnapping: Peri gets kidnapped by the English Duke of Buckingham, because everyone mistakes her for Queen Anne.
- Batman Gambit:
- Erimem bluffing the Musketeers gives the Doctor an audience with the king.
- The Duke of Buckingham pulls one as well, trying to kidnap the Queen Anne disguised as the Cardinal's men, turning Church against Crown.
- Battle Cry: Erimem creates a unified force of the Musketeers and the Cardinal's Guards who use "For the church and the crown!" as their battle cry. The Doctor attempts to introduce the Musketeers to "One for all, and all for one!" as theirs, only to be told It Will Never Catch On.
- Buffy Speak: Metal pointy thing.
- Call-Back: An inverted phrase of "The King's Demons".Buckingham: "You wish to take on the finest swordsman in England?"The Doctor: "Hasn't anybody told you!? We're in France!"
- Cats Are Mean: The Doctor is at one point unable to properly set the TARDIS controls because Erimem's cat is lying on the control console.
- Continuity Nod: The Doctor can't handle the cat Erimem brought and wishes K9 was with him.
- Contrived Coincidence: Peri arrives in Paris just in time to be mistaken for the delayed Queen Anne and be captured in her place as part of Buckingham's plot.
- Crash-Into Hello: The Doctor meets The Three Musketeers, in a scene that's a loving Homage to the original.
- Dressing as the Enemy: Buckingham's men abduct "Queen Anne" dressed as the Cardinal's guards. Later the Doctor's musketeer allies don stolen uniforms to infiltrate Buckingham's fortress to rescue the Doctor.
- Distressed Dude: Five gets strung up in strappado. Luckily for him, he's Made of Iron, but it's still very painful.
- Duel to the Death: Outlawed by the King, but the Musketeers still try to invoke this when they bump into the Doctor.
- Everybody Lives: Well aside from one Mauve Shirt, though it's very uncommon for Five, who's used to stories where everyone dies. He even mentions he thought the adventure was "Fun" at the end of the day.
- Evil Chancellor: The Cardinal is a downplayed version; he's not so much evil as pragmatic and having to deal with an increasingly childish Louis. Also he differs from other versions in that he's very dependent on Louis for his power despite the King's deliberate immaturity.
- False Flag Operation: Buckingham stages a series of attacks designed to have the Musketeers and Cardinal's Guards at each other's throat so no one will be in a position to prevent his troops invading Paris.
- A Father to His Men: The Cardinal laments Captain Morand's death.
- Fish out of Water: Completely averted with Erimem. Sure, she has trouble understanding a lot of phrases and social conventions, but she knows exactly how to deal with uppity Kings, armies that need encouragement, and heroic sword fights.
- Guile Hero: Erimem knows her way around court etiquette, and instantly charm herself into the King's court. She's very good.
- Have We Met Yet?: The Doctor says he's met King Louis before later on in Louis' life, but since he's had "a nip and a tuck" since, it shouldn't be an issue.
- Historical Domain Character: King Louis XIII, Queen Anne, Cardinal Richelieu.
- Identical Stranger: Peri and Queen Anne. (Actor Nicola Bryant uses her natural English accent for Queen Anne.)
- It Will Never Catch On: The Doctor tries to introduce the Three Musketeers to their "all for one, and one for all!" Badass Creed Catchphrase.
- Karma Houdini: Despite being the driving plot behind the entire adventure, Lord Buckingham manages to keep this entire affair a secret because it might kick off a war. (He does meet his maker years later at the hands of John Felton).
- Look Behind You: "Say isn't that the Cardinal running naked through the street!?"
- Mistaken for Spies: Buckingham is convinced that the Doctor is foreign spy, and tortures him in an effort to find out who he is working for and how much he knows.
- Mugged for Disguise: Rouffet and Delmarre knock out three of Buckingham's soldiers and steal their uniforms so that the two of them and Peri can infiltrate Buckingham's chateau to look for the Doctor.
- Reasonable Authority Figure:
- King Louis, to his musketeers at the very least.
- Richelieu, at the end. he arranges for Buckingham's attempted invasion to be covered up so to avoid a war with England. This also stops the story from contradicting history.
- Rousing Speech: Erimem delivers one to unite the Musketeers and the Cardinal's Guards into a cohesive force to fight Buckingham's troops.
- Show Some Leg: Peri distracts the guard outside the Cardinal's cell by asking him what he thinks of her boots.
- Stealth Pun: After Richelieu is thrown into the dungeon, Anne remarks that the most powerful man in France is now locked up underneath the floors. It's a blink-and-miss joke, but she could also be referring to The Man in the Iron Mask.
- Take That!: The episode is pretty much a big giant Take That to the way The Three Musketeers re-interpreted historical people. The Doctor laments that Dumas refused to listen to his suggestions.
- Those Two Guys: Rouffet and Delmarre, the two musketeers who initially challenge the Doctor to a duel, then get dragged along in Peri's wake for most of the adventure, before finally fighting alongside Erimem in the battle against Buckingham; keeping up a stream of banter the entire way.
- Title Drop: "For the church and the crown!" becomes the Battle Cry of the united force Musketeers and Cardinal's Guards.
- Too Dumb to Live: The Doctor is unarmed, so he can't duel. A Musketeer offers him one, and he accepts it out of politeness, not knowing what he's gotten himself into.
- Tunnel Network: When the Doctor suggests an alternative way into the palace when the doorman won't let them in, Peri anticipates a smelly tunnel.