Spoilers ahead! Scroll down at your own risk.
In what is now known as "Year 0", a boatful of refugees arriving in Spain brought an unknown contagious disease with them that was dubbed "the Rash Illness", after what was thought to be its main symptom. Governments around the world became aware of its fast spread but few believed it would do much harm. Wisely, Iceland closed its borders only 3 days after the Rash's initial discovery and was the first country to do so, but most other countries failed to follow suit in time. By the time it became clear that infected were in for much worse than a simple rash, the time to prevent the spread of the illness had already passed.
In the comic's present time, Year 90, the leftovers of the five largest Nordic countries have re-established contact with each other, but are oblivious towards the state of affairs elsewhere in what is now called "the Silent World". Iceland, which did implement and enforce national isolation in time, is the largest "safe area" in the Nordics and houses almost 80% of the remaining population - in spite of having lost about one third of their year 0 headcount as well.
"The Rash" has apparently continued to evolve into "the Illness", which fills the Silent World - including most of the former territory of the other four Nordic nations - not only with the possibility of infection and death, but also murderous monsters that are the result of animals and humans (un)lucky enough not to have died after infection. The percentage of humans who have immunity against the Illness is rising, partially with the help of the Dagrenning Program, but encounters with monsters lead to fights to the death for all unfortunate enough to meet with them. A special branch of the military, the cleansers, works on winning back habitable areas from the bestiary.
Overcoming reluctance on the part of the government, a group of four organizers has obtained permission to finally send an expedition into the Silent Lands, though the actual purpose of the endeavour is to obtain antiquities - books, to be precise - to sell and gain a fortune with. The task of actually putting their lives on the line has, naturally, been handed to someone else - five adventurers selected for the specific purpose of being a cheap, expendable workforce.
Leaving the Known World by way of the Öresund bridge (which broke in the process), the expedition started checking libraries in Kastrup, a suburb of the former Danish capital of Copenhagen. So far, the results are mixed, and not quite up to expectations, and a mishap that took place while the team tooled up forced them to interrupt book-scavenging and deal with an unexpected lack of rations.
Another series of mishaps then hands them only a small amount of food, and a sixth mouth - a civilian stowaway - who has no more choice left but to stick with them, likely for the entire length of the mission. Furthermore, a run-in with ghosts inhabiting Old-World infirmaries in Amalienborg and Kastrup, which proved to be more dangerous than expected forced them to leave Copenhagen prematurely.
A medical discovery, however, sends them across a several-week trip across Sjaelland and Fyn, scavenging for books on their way to Odense University Hospital (OUH) to find a possible treatment or cure for the Rash. Unfortunately, however, the ghosts remain on their trail, revealing a dangerous tenacity that ultimately concludes in a curb-stomp ambush (after finding the "cure" ineffective at that). The crew face a herd of ghosts, trolls and beasts that they survive only through remote magic interference, but it becomes a pyrrhic victory when Tuuri is attacked by a troll that breaks into the tank.
Several days later, with the tank in poor repair but functional and Tuuri now in quarantine, they continue their journey toward the pre-arranged extraction spot, crossing into mainland Denmark with the ghosts, albeit weakened, still close behind. It is near the city of Vejle that the tank's motor catches on fire after a series of breakdowns. While the crew prepares for walking, leaving behind much of their loot, Tuuri discovers that she is infected with the Rash, and drowns herself in Vejle Fjord, unnoticed by Lalli and the crew until it is too late. She is guided into the afterlife by the Swan of Tuonela.
After Tuuri's cremation the team splits up: Lalli remains behind with Emil waiting for him, to make certain that Tuuri found her way. While they attempt to catch up with Sigrun, Mikkel and Reynir, a giant's attack leaves Lalli comatose and lost outside his body, and casts the two of them away down Vejle Fjord, coming ashore too far away to rejoin the rest of the team. Believed dead, the two groups now make their separate ways toward the pickup spot. Meanwhile, Lalli's spirit is taking refuge in Emil's mind.
Sigrun is the one most visibly affected by survivor's guilt after finding the remains of the dead giant, but no sign of Emil and Lalli. That and her infected arm cause her to collapse and ask to be left behind. She continues the journey on the wheelbarrow with the books. In the meantime, Lalli's mage skills make Emil vulnerable to trolls' mind control attempts, and it takes drastic measures from Lalli's side to save them both. Both teams share a heart-to-heart that evening that deepens the bonds between the characters.
A while later, Reynir remembers a vision from some time prior and finds Pastor A.'s church, where she is still living - in form of a huge (but harmless) troll. The crew also discovers skeletons laid out in the pews who ostensibly died of the failed cure but are no longer present as ghosts. That night, the ghosts also arrive at the church to be welcomed by the Pastor. She comforts them, and all of them depart into the afterlife while Reynir watches from a distance. The church subsequently collapses. In the morning the wheelbarrow team continues on their way and arrives at the pickup spot without further incidents.
Memes, Plot Points and Running Gags Edit
Apart from characters' individual traits, there are a couple character-spanning topics that appear repeatedly. First and foremost, the five nations still have their individual languages, and the ensuing communication barriers certainly help them keep their old preconceptions about each other - as well as the occasional new one.
Another recurring topic is the ancestry of the protagonists, more precisely, how they are descendants of the various characters that appeared in the prologue.
A central topic in the making - now that the expedition has left the Öresundsbro Base and entered the Silent World - is the "Cat-Tank", the expedition's mobile base of operations (and, presumably, shelter from the ubiquitous dangers).
Heart shapes have appeared quite a number of times in the comics, from Mr. Pedersen's tie in the prologue to the Lumilintu's decor to jewelery on the giant attacking the Dalahästen to Cthulhund's collar, the latter two leading to speculation that Cthulhund was a pet of the woman who brought said jewelery into the giant. Another theory is that the symbol has been inspired by the Danish coat of arms, but note that only half of the appearances (Mr. Pedersen and Cthulhund) are related to Denmark.