Secret agents Mortadelo and Filemón are called to TIA headquarters to meet a dangerous mission. Dr. Bacterio has developed an experimental insecticide sulfate to eliminate pests, but the chemical instead makes the insects grow to titanic proportions, potentially endangering all of mankind. A bottle of this sulfate had been stolen by agents of the Republic of Tirania, an European country ruled by brutal dictator Bruteztrausen, who plans to mass-produce the sulfate in order to create an army of giant insects to conquer mankind. It is up to Mortadelo and Filemón to infiltrate in Tirania and recover the item.
This comic marked the first appearance of all the iconic elements of Mortadelo y Filemón: the TIA, the Supervisor Vicente, Dr. Bacterio and the worldwide reach of the title duo's missions. It is considered one of the greatest stories, both by its elaborate plot and its drawing quality, which came from Ibáñez's desire to imitate the rich style of Franco-Belgian Comics.
Being one of the series' peaks, it was adapted in the legendary Mortadelo and Filemón animated series and later received its own videogame, which was the breaking hit of developer Alcachofa Soft. The 2003 live action film also took many plot elements from this story.
This comic provides examples of:
- Agony of the Feet: Filemón gets his feet trampled by a tank when he stops in the roadside with his shoes off to rest. Later Rino gets his own when he steps on a spike.
- Bait-and-Switch: A trademark of Ibáñez, not used any less in this case. The very story opens with the title characters walking to their headquarters, which seem to be a magnificent government building... only to be revealed to be actually a small working shack next to the place. The joke then sees another iteration, as the shack is revealed to be the secret elevator entry of an underground facility, only for it not to be so secret after all given that burglars have somehow stolen the elevator itself. It only goes on and on, with the Supervisor giving them plane tickets which are actually tickets for a cheap bus brand named The Plane.
- Bald of Evil: Otto Rino, Tirania's secret police chief, has one of those.
- Berserk Button: When Mortadelo recounts how Bacterio made him lose all of his hair, the doctor retorts lightly a Spanish idiom meant to make peace. The thing is that said idiom makes reference to hair of all things, which gets Mortadelo angry enough to need Filemón to contain him in order not to attack Bacterio.
- Big Creepy-Crawlies: The sulfate turns regular insects on this. Among the giantized bugs in the story there are bees, beetles, grasshoppers, spider, ants and scorpions.
- Black Comedy Burst: When Bruteztrausen's tanks start firing, a shell hits a farmer that was busy steering a pig. The farmer ends up comically singed, while the pig is turned to sausages in his hands.
- Book Ends: At the beginning of the story, Mortadelo and Filemón get injured by a fall when they step into an empty elevator shaft, as the elevator itself was stolen. At the end, it happens again, with the Super (who also got injured the same way both times) revealing they actually brought a new elevator which got quickly stolen again.
- The Cameo: Rompetechos makes one, in which he is revealed to have somehow become Tirania's new president.
- Clothing Damage: Gradually, Filemón gets his clothes shredded and more damaged as the story goes, from each physical misfortune to happen to him along the way. Interestingly, his clothes actually stay damaged; later books would just have them regenerate back to normality after each violence gag takes place.
- Collateral Damage: Mortadelo summons a giant dung beetle while fighting Tiranian frontier guards, but the beast ends up destroying a post, where Filemón is being held, in order to make a ball with it.
- Contrived Coincidence: Bruteztrausen orders a tank to run over a tree on the roadside, and this tree happens to be a disguised Mortadelo hiding Filemón between his branches.
- Crazy-Prepared: Tiranian peasants are all ready for war to a comical degree, with a man even carrying a warhead in his car.
- Crouching Moron, Hidden Badass: Mortadelo is generally almost as dense in this story as always, but he actually defeats a fair share of enemies thanks to his disguises, the title sulfate and some quick wits.
- Cunning Linguist: Subverted. Filemón speaks Tiranian language (which in this case is half-mock, half-real German), but his knowledge fails him a couple of times. Mortadelo is even worse, as he once blows up his cover as a Tiranian general because he cannot talk Tiranian at all.
- Early-Installment Weirdness: Mortadelo and Filemón (or rather Mortadelo) are in their most badass in this story, as they practically smash their way through Tirania and end up not only fulfilling their given mission, but also destroying the menacing Bruteztrausen dictatorship in the process. Later stories characterized them as much less competent, to the point they rarely get anything right nowadays.
- Driven to Madness: At the end of the story, Bruteztrausen goes insane after all the mess, the breaking point being his tank division getting wrecked by giant ants. Supplementary materials reveal he never recovered and went to die not much later.
- Drives Like Crazy:
- Mortadelo wreaks havoc with a power shovel for a very prolonged time, though all by accident given that he was just seeking the controls. It destroys Bruteztrausen's limo and hurts the dictator in several ways, among other deeds.
- Subverted later, when Mortadelo crashes a military vehicle in order to avoid a rabbit.
- Epic Fail: Mortadelo disguises himself as a construction worker in order to spy in a building in construction. It takes three hours for him to do so, returning all tired, as he was quickly given work to do when he was spotted.
- The Guards Must Be Crazy: Tiranian soldiers vary wildly in competence, some of them being quite sharp while others are classical idiots. A particularly dumb frontier guard, when spotting Mortadelo hopping the barrier disguised as an ostrich, opts to go ask his superior whether ostriches need license to pass.
- Identical Stranger: A random cop in Tirania looks just like the Super, only maybe slightly less stout, but this is never commented on.
- Instrument of Murder: A trombone is used to momentarily disable a Tiranian citizen.
- Literal-Minded:
- Mortadelo and Filemón are trying to exit a sewer when the latter asks if there are cars or any danger, and Mortadelo denies it, so Filemón comes out confidently, only to be run over by a truck. The point here is that Filemón had used an Spanish medieval idiom meaning whether there was danger or not ("are there any Moors in the coast?") and Mortadelo understood he was asking about its literal meaning (claiming that there were cars, but not Moors).
- Filemón doesn't know how to enter Bruteztrausen's palace. Mortadelo's solution? Shouting anti-Bruteztrausen slogans right in front of the guards, getting the duo promptly arrested. Enter the palace, he said.
- The worst example might be when Rino and Bruteztrausen grab a car to try to chase Mortadelo and Filemón. As the dictator keeps screaming to march forward, even despite Rino's doubts, the latter starts up the car and literally drives it right forward against the wall it was parked towards, crashing the vehicle and injuring them.
- Make My Monster Grow: Bruteztrausen intends to do this with the sulfate.
- Militaries Are Useless: Downplayed, as there are competent people in Tirania's army, but many of them are not. The crewmen of its main tank division, for instance, are epically bad at their task, so much that the division ends up half destroyed by their own incompetence before Mortadelo unleashes a giant ant force on them.
- People's Republic of Tyranny: Tirania, whose name hilariously gives it out. There are several signs with friendly messages in the road leading to their frontier, but the frontier itself is a barbed wire zone with mines, tanks and even ballistic missiles pointing outwards.
- Putting on the Reich: Tirania is obviously meant to be a very thinly veiled Nazi Germany, down to their language and uniforms.
- Refuge in Audacity: To Filemón's desperation, Mortadelo proposes to cross the Tiranian customs post by donning animal costumes and just strolling by. It actually works pretty well for him, but Filemón has less luck and is captured.
- Satchel Switcheroo: Mortadelo snatches sneakily the sulfate bottle from Bruteztrausen's hand and replaces it with a turtle before the dictator realizes. Bruteztrausen then uses the critter to club Rino for not having realized himself.
- The Scrooge: Apparently, Filemón is one, which Mortadelo exploits to get him out of the ball of rubble created by a giant dung beetle. He throws a coin nearby in what he calls the "X-B-7 method", and Filemón jumps out of the ball, entirely energized, in order to catch it.
- Shout-Out:
- The story is a Whole-Plot Reference to Hergé's Tintin: The Calculus Affair and Maurice Tillieux's Gil Jourdan: The Three-Fingered Glove, with a lot of references to the latter among its gags. Spirou & Fantasio also inspired it.
- The weird military vehicle hijacked by Mortadelo is a direct reference to one seen in Peyo's Benoit Brisefer, specifically the story The Special Agent.
- Several landscapes from Tirania were inspired by Spirou and works by André Franquin. Sophie by Vicq and Jidehem also lent some images.
- Shovel Strike: A cop suffers an exaggerated version when Mortadelo accidentally hits him over the head with a power shovel.
- Sizeshifter: The effects of the sulfate over insects, aside from sometimes killing nearby plants.
- Spider People: When Mortadelo sprays sulfate on a spider in order to disable a Tiranian jailer, the resultant giant spider is drawn with the face of an old woman, just for the kicks.
- Story-Breaker Power: The sulfate spray given to Mortadelo and Filemón ends up being vital to defeat Tirania, as Mortadelo uses it constantly to summon giant insects that wreak havoc.
- Surprisingly Happy Ending: Unusually for a MyF story, this ends in complete success: the sulfate is recovered, the militaristic Republic of Tirania is overthrown (accidentally and not part of their mission, but still), and Bacterio destroys the dangerous chemical. The only drawback sees the four TIA agents being hilariously attacked by the last insect affected by the sulfate.
- Those Wacky Nazis: Tiranians, of course. Several character types of the list are used in this story.
