The comic adds a fictitious Chapter 24 (XXIV) titled "Defeats at the Hands of the Indomitable Gauls of Armorica" to Julius Caesar's Commentaries on the Gallic War. Caesar's publisher, Libellus Blockbustus, deletes this chapter, fearing it would besmirch the Roman leader's curriculum vitae. A mute Numidian scribe, Bigdhata, steals a copy of the chapter and gives it to the journalist Confoundtheirpolitix, who in turn passes it on to the village of indomitable Gauls.
Chief Vitalstatistix is unfazed by the lie that all Gaul has been conquered by the Romans, but his wife Impedimenta urges him to campaign for the truth. Since the Gauls have, unlike the Greeks and Romans, no skills in reading and writing, the druid Getafix (accompanied by Asterix, Obelix and Dogmatix) travels to the forest of the Carnutes to meet his former teacher, Archaeopterix, who will then pass on the truth by word of mouth to future generations. The true story eventually reaches René Goscinny and Albert Uderzo in a French cafe, who publish the censored tales in comic books as the Asterix adventures.
Asterix and the Missing Scroll provides examples of:
- Accidental Misnaming: Archaeopterix just can't get the names of Getafix, Asterix and Obelix right.
- Actual Pacifist: Obelix, of all people, becomes one after his horoscope tells him to avoid conflict. Good thing the Romans are so scared of him that they turn and run when they just see him, and don't believe him when he says he means no harm. He gets over it when it's revealed his horoscope got mixed up with that of Geriatrix.
- Aesop Amnesia: Despite what happened to him the last time he drank the magic potion, Obelix still asks Asterix to give him some (and is clearly annoyed when Asterix says no).
- Anachronism Stew:
- The messages send by pigeon are kept short and with a lot of abbreviations, just like modern day text messages.
- The Roman world apparently has newspapers (the first newspapers were published in Germany in the 1600s) complete with horoscope page (originally popularised in the UK in the 1930s).
- Arboreal Abode: The great druid Archaeopterix's house is build inside a gigantic oak tree. Complete with water mill.
- Bears Are Bad News: When the Romans follow the Gauls into the forest of Carnutes, Anachronistix sends a bear after them, which mauls them easily and comically.
- The Beastmaster: The druid Anachronistix has a flute that allows him to summon and command animals. He instructs a squirrel to guide Asterix, Obelix and Getafix through the forest of Carnutes, and summons a bear to chase away the Romans.
- Continuity Nod: Chapter 24 of Commentaries on the Gallic War contains references to various previous Asterix albums.
- Direct Line to the Author: The post-scriptum of the story implies that the Armorican village truly existed, and the comics are based on stories passed on through the generations, which René Goscinny and Albert Uderzo eventually picked up.
- Epic Hail: Cacofonix has a special instrument called the Moomoophone for this purpose. When the Romans show up in large numbers at the village to demand the scroll back, he uses it to send a warning signal, which is passed on by other Gauls who hear it, until it reaches Asterix, Obelix and Getafix in the forest of Carnutes.
- Every Episode Ending: Averted; Getafix is the one not participating in the banquet since he's tired and has fallen asleep under a tree. Cacofonix is present at the table (presumably because he was responsible for saving the day), but refrains from playing his Moomoophone when Fulliautomatix alerts him to the sleeping Getafix.
- Exact Eavesdropping: A Roman hiding in a tree overhears Asterix, Obelix and Getafix when they openly discuss their plan to bring the scroll to Archaeopterix.
- Failed a Spot Check: When Confoundtheirpolitix goes to meet "Caesar" at the camp of Totorum, he somehow completely misses that the entire garrison is standing behind him while he observes the deserted camp.
- Going for the Big Scoop: Confoundtheirpolitix constantly looks for new scoops. Hence why, when a message supposedly from Julius Caesar himself arrives that he wants to talk, Confoundtheirpolitix eagerly accepts the invitation despite warnings from Vitalstatistix that it is a trap.
- Green Around the Gills: Blockbustus turns green in fear when news that the Indomitable Gauls now have the scroll reaches him.
- Grievous Harm with a Body: Obelix happily does this, with a Roman in each hand, during the final fight, after finding out he doesn't have to avoid conflicts after all.
- Horrorscope: Obelix's horoscope, as read to him by Wifix, states that he should avoid conflict and go easy on the roast boars. For a fight-loving Big Eater like Obelix, this news outright terrifies him. Nevertheless, he tries his best to stick to the advice, until it's revealed his horoscope was mixed up with that of Geriatrix.
- Instant Messenger Pigeon: Played With. The Romans make great use of these. The narration even calls it the latest communication technology, and it's shown to be more effective than the traditional mail, which is transported by ox-cart. However, that this technique is not exactly fault-proof becomes clear when first a pigeon carrying a message to Rome accidentally ends up on the ship of the pirates, twice a Roman accidentally releases the pigeons before they can attach the messages to them, and in the end a pigeon delivering the message that Caesar is on his way to Armorica arrives after the fight is over and Caesar has already left again.
- I Should Write a Book About This: As told below, the content of the lost chapter finally reaches the ears of Goscinny and Uderzo in the 20th century, who of course conclude they must do the first written version of it.
- Minion Maracas: Libellus Blockbustus is a choleric little man who's in the habit of shaking his servants. Including with a mute scribe, while ordering him to talk (he has to be reminded twice that the scribe can't).
- Mobile Shrubbery: The Romans once more use this technique when having to spy on the Gaulish village. One, a new recruit, opts for a spruce disguise instead of the classic bush, and is mocked for it by the others.
- News Travels Fast: When Blockbustus is summoned to Caesar's palace immediately after receiving news that the Indomitable Gauls now have the scroll, he fears that this trope is in effect and Caesar already knows about it. Fortunately for him, the trope is averted.
- Noodle Incident: Archaeopterix brings up an incident when Getafix made the flowers of spring bloom in Archaeopterix's breeches. Asterix and Obelix have a good laugh about it, much to Getafix's dismay.
- Nice Job Fixing It, Villain: One of the Romans tasked with getting the scroll back accidentally releases the messenger pigeons too early, which warns the Gauls that they are being followed.
- Older Is Better: Archaeopterix keeps an archive of all potions ever made by druids, including the magic potion. After being infused for so many years, the archived potion is notably stronger than a freshly made batch. It grants Asterix and Getafix Super-Speed even greater than that of Obelix, and it cures Getafix's bad back.
- Oral Tradition: Getafix points out that this is the main way the Gauls, and Druids in particular, preserve their history and stories, since writing is more something the Greeks and Romans do. Hence why he suggests that the scroll should be brought to Archaeopterix so he can memorize it. It proves effective enough to keep the stories of the Indomitable Gauls alive till the present day.
- Pajama-Clad Hero: Downplayed, but the protagonists have a meeting in the middle of the night, all still in their nightwear, when Impedimenta convinces Vitalstatistix that the stolen scroll and Caesars attempt to hide it cannot be ignored.
- Politically Incorrect Villain: Libellus Blockbustus, who holds great contempt for the Numidian scribes. When informed that a scribe secured a copy of chapter 24 because he solidarized with the Gauls, Blockbustus states "A thinking scribe? Tell me another!"
- Punny Name: In addition to everyone mentioned elsewhere on the page, one of the legionaries who has to guard the messenger pigeons is called Antivirus.
- Ripped from the Headlines: The story is one big shout out to the whole Wikileaks scandal.
- Running Gag:
- Geriatrix trying to go on "new conquests" once his horoscope tells him he will do so.
- Blockbustus absolutely not wanting to touch the grass in Gaul, stating it gives him the willies.
- Secret Weapon: Apparently, according to Vitalstatistix, the Gauls keep Cacofonix around as part of their emergency measures, in case the Romans attack while Getafix is away. Hence why they'd keep up with him despite his bad singing. Not only is his bad singing powerful enough to stall the Romans for a while and stop threats that can't be beaten by punching, as shown in previous comics, but he also informs other bards and can inform Getafix from everywhere as well.
- Sequel: Discussed. Caesar is so satisfied with the success of his book that he plans to write a sequel, "War with the Gauls II".
- Shown Their Work:
- The genuine Celtic tree-zodiac is used for the absurd anachronism of the Gauls reading their horoscopes in the newspaper.
- The story refers the real life fact that Celtic culture was based on oral tradition instead of writings.
- The Speechless: The Numidian scribes (ghostwriters) that helped publish Caesar's Commentaries on the Gallic War are all mute. This comes back to bite Blockbustus when he tries to interrogate the Numidian that gave a copy of the forbidden chapter to a Gaul.
- The Stinger: After the panel showing the banquet, there is a post-scriptum section that shows how the tales of the Indomitable Gauls eventually reach modern times, and are picked up by Goscinny and Uderzo.
- Throw the Dog a Bone: The pirates appear in this story, but for once they do not run into the Gauls or lose their ship.
- Unicorn: The Gauls encounter a few of them in the forest of Carnutes. Later, the Romans following the Gauls are attacked by one.
- Visual Pun: Numidian scribes are employed as ghostwriters. Historically, Numidians were ancient Berbers living in nowaday northern Algeria, and are always drawn as black characters in Asterix books. In French, the common word for "ghostwriter" is "nègre littéraire" ("literary negro").
- Wheel o' Feet: Asterix, Obelix and Getafix when they run back to their village at superhuman speed (thanks to the magic potion).
- Written by the Winners: At the suggestion of his publisher, Libellus Blockbustus, Caesar decides to make no mention of the Indomitable Gauls of Armorica. Since the Gauls are (mostly) illiterate, they won't be able to protest or correct him, so Caesar's version of history will be the only preserved one.
