Medusa, a deadly virus becomes a worldwide epidemic. In order to escape from this deadly virus, a handful of people are chosen to be put into a cold sleep, laying in a capsule hoping for the future cure. Kasumi, a teenage girl is one of the 160 chosen for this procedure, and is guided to a Cold Sleep Capsule Center (CSCC) inside an ancient castle. Understanding that it is hardly possible, Kasumi goes to sleep still anticipating for a reunion with her twin sister Shizuku, who also is infected with the virus. As Kasumi and the others awake, they notice that the CSCC is not as they remembered. Just like the story of Sleeping Beauty, the castle is covered with thorn, and the awaken are attacked by unknown creatures and monsters! How long were they asleep? Where did the monsters come from? What has happened to the world? Abandoned in the midst of an enigma, the escapade of the seven survivors begins... (Source: kingofthorn.net)

Compilation film of the second half of the TV series.

Half a year has passed. Arriving in the Iron Fortress, Ikoma and Mumei set foot in Unato: another ravaged zone that fell into the grip of the deadly Kabane. In this war-torn zone, the group fends off more dangerous Kabane that are attacking with patterns they had never seen before. The Iron Fortress crew eventually meet up with a survival group which requests their aid in reclaiming the zone. The newly forged alliance ventures deeper into the area of the castle and investigates the peculiar case of these new Kabane. But their search for answers unearths truths that are far more horrifying than they imagined. Forced to confront the reality behind the Kabane, Ikoma, Mumei, and their allies come to realize the despair buried within Unato.

The world is in the midst of the industrial revolution when horrific creatures emerge from a mysterious virus, ripping through the flesh of humans to sate their never-ending appetite. The only way to kill these beings, known as Kabane, is by destroying their steel-coated hearts. However, if bitten by one of these monsters, the victim is doomed to a fate worse than death, as the fallen rise once more to join the ranks of their fellow undead. Only the most fortified of civilizations have survived this turmoil, as is the case with the island of Hinomoto, where mankind has created a massive wall to protect themselves from the endless hordes of Kabane. The only way into these giant fortresses is via heavily-armored trains, which are serviced and built by young men such as Ikoma. Having created a deadly weapon that he believes will easily pierce through the hearts of Kabane, Ikoma eagerly awaits the day when he will be able to fight using his new invention. Little does he know, however, that his chance will come much sooner than he expected...