In Condatum, a Roman Quaestor named Vexatious Sinusitus is investigating the actions of corrupt Governor Varius Flavus when he is poisoned by his quarry. He has, however, heard of Getafix from Ceasar's epileptic rantings and sends his guard to fetch the druid. Bound always to help the sick, Getafix goes to Sinusitus accompanied by Asterix and Obelix. He soon realises what has happened, though he keeps this from Flavus. Getafix can cure Sinusitus, but the cure requires the silver star (now known as the edelweiss), a rare flower that grows only at very high altitudes
, and so dispatches Asterix and Obelix to Helvetia (or Switzerland as we call it today) to find one. In the meantime, Sinusitus will go back to the Gaulish village, supposedly as a hostage to ensure Asterix and Obelix's safe return, but actually to get him away from Flavus. Nonetheless, this gives Flavus an extra reason to want to stop Asterix, and he sends a messenger to Genava, the capital of Helvetia, to ask the local governor Curious Odus (an old friend, and equally corrupt) for help.
In Helvetia, the two Gauls find themselves constantly chased by Odus' troops, but evade them with the help of some friendly Helvetians. Eventually, they come to the mountains and begin climbing. Unfortunately, Obelix is in a drunken stupor by this point, but a group of Helvetians help Asterix to pull him up behind them (together with a Roman legionary who grabbed Obelix's hand at the bottom and spends the entire climb clinging on in desperation). They finally find a silver star and continue to the top: Gaul is an easy descent of the other side of the mountain away.
Back in the Gaulish village, Varius Flavus arrives to pretend to be upset about Asterix and Obelix not getting back and the Gauls having to kill their hostage — at which point a fully-cured Sinusitus emerges from Getafix's hut and punches Flavus into the sky, telling him that, when he lands, he'll be thrown to the lions along with Curious Odus. Sinusitus then becomes the first-ever Roman to join the Gauls at their traditional banquet.
- Bamboo Technology: The "Cuckoo" clocks.
- Blessed Are the Cheesemakers: It's Helvetia. Of course. A big wheel of cheese is even featured on the cover.
- Cool and Unusual Punishment: For losing your piece of bread in the cheese Fondue for the third time.
- Continuity Nod: Geriatrix still has the club he took from Magnumopus in the climactic battle in the previous album, Asterix and the Roman Agent.
- Corrupt Politician: Flavus.
- Flower from the Mountaintop: Asterix and Obelix have to pluck one. The flower is of course edelweiss.
- Foreshadowing: After swimming and climbing a mountain to get Asterix and Obelix one Roman complains about doing all this activities. His centurio snaps back: "We're not taking a holiday here." Amusing, because today both swimming and mountain climbing are holiday activities in Switzerland.
- When Asterix uses Obelix' body to slide down the snowy mountain he references another popular Swiss sport and holiday activity: snow sliding and/or skiing.
- Heavy Sleeper: Obelix misses most of the excitement, sleeping through climbing a mountain and several battles. His description of Helvetia after the fact is "Flat."
- National Stereotypes: The Helvetians (Swiss) are portrayed as punctual and obsessed with keeping everything clean. They are also seen playing Alpine horns, yodeling and eating cheese.
- Neat Freak: Most Swiss people shown, something that many would call Truth in Television.
- The Red Cross: One Helvetian beats up a Roman and puts him in bandage afterwards, explaining "it's their duty to take care of all victims, whether they are enemies or not." This is a reference to the International Red Cross, which was founded by a Swiss, Henri Dunant.
- Running Gag: Every time the possibility of eating boar's tripe fried in aurochs' dripping is mentioned, someone will excitedly ask, "With honey??" At one point, one of Flavus' guards falls into a cauldron of cold boar's tripe fried in aurochs' dripping, and as he eats the contents, he asks if anyone has a spot of honey.
- Save the Villain: Getafix decides to help curing a terminally ill Roman, despite the fact that Romans are usually their enemies.
- A Swiss beats up a Roman, then gives him medical aid afterwards, because even their enemies should receive medical help.
- Asterix and Obelix have their tire changed by Antar, the mascotte of the French service station Antar. In the English version he is changed by Bibendum, the mascotte of Michelin.
- The orgy scenes at Varius Flavus' palace in Condatum are a spoof of similar scenes in Federico Fellini's film Satyricon.
- Swiss Bank Account: Where Asterix and Obelix spend the night without being bothered by Romans.
- Take That: The palace of international conferences where Asterix, Obelix, and Petitsuix hide from the Romans is a reference to the various international peacekeeping organisations with headquarters in Geneva. Given that the floor is held by a delegate giving a long-winded speech that has bored most of his audience to sleep, we may conclude that Goscinny and Uderzo were not impressed by such organisations! Or just political organisations in general.
- Tampering with Food and Drink: Varius Flavus poisons Sinisitus' vegetable soup to keep him from discovering how much he has been skimming off the top of the taxes he is supposedly collecting for Rome.
- William Telling: Asterix does some archery and hits a bulls-eye, just narrowly missing an apple balanced on a boy's head. Spectators were impressed, but felt something was missing.
- Windbag Politician: The peacekeeping conference is a bunch of tribal chieftains speaking in turns to wake up all the others.
- Yodel Land: A very romanticized version of Switzerland is shown here, with all the Alpine clichés thrown together.