The kingdom of Morz is the northernmost kingdom in the world: once covered in ice; it’s no longer the case since the mysterious fall of entities that made the eternal snow melt; winger lions, unknown to all civilizations. After this event, humanity could settle down durably in the region, to the detriment of the natives: witches and N’dus, a bestial civilization on decline.

Five hundred years old have passed and Noir is a well-known menace in the kingdom; feared by all and especially by prince Jaroslav. The latter replaced his older brother, who passed away, on Morz throne after living in a minor household safe from threats; real or not. He is deeply faithful, and really takes at heart the abuses of Noir and its Second, while struggling to establish his own authority on his kingdom and court, particularly with his mother, the queen. Only his champion supports him indefectibly in those troubled times. He’s convinced to be one of Light’s elect and his mother counts on him to maintain control over the throne. However, a secret weighs on the royal family: the corpses of the lions fallen centuries ago are kept in a part of the castle and are used to maintain the summer on the kingdom with a magic phenomenon which dates back centuries: eating their flesh. The Second that haunts Morz next to Noir is Agnieszka, a tough woman with unsettling white hair, who has assisted the mysterious Noir for years. Her cruelty is legendary, but is only a façade. Her master, Noir, is a changing being, unpredictable, closer to be a fallen spirit than the tyrant it pretends to be. It dreams more insane than the conquest of the kingdom: to bring back the winter on those forsaken lands, with the help of witches and N’dus. Agnieszka gives him an unfailing support since the first day, ignoring the reasons that drove her to follow it, but she begins to have doubts; what if all there is in Noir is madness?

The other humans that follow Noir, each with their reasons, are secretly convinced of it. While continuing to prepare future offensives, Agnieszka is worried about Noir's loyalty to the witches, their only true allies, which Agnieszka despises for their mysticism. Nevertheless, she respects the odd bound that they share with their totem, the animal with which they linked themselves for life, especially since she knows herself being a witch, as it can happen from time to time in the human people exiled in those lands for centuries. However, Agnieszka doesn’t know which animal could be her totem and doesn’t care about it. She only lives for Noir, as they live to see winter once again and to regain their past greatness. Noir succumbs to the recommendation of a witch who came to negotiate with them, and who persuade it to attack the port city of Vilnia for a mysterious scheme.

Meanwhile, the veil is lifted on the possible causes of the prince's underlying madness, because queen Honorata feeds her son in secret with pieces of the fallen winged beasts’ corpses from centuries ago. Agnieszka doesn’t have a choice but to accomplish the will of the witches in Vilnia, while battling in a fair duel with the prince champion, who immediately falls in love with her. She collects the loot, which will actually serve for a young witch who stays with Noir because of her mistrust of her own people. Hidden in a sack of grain, the latter will find her own totem and will be forced to live with the witches. These ones schemed all of this to recover enough power to cast a night spirit under the form a baby corpse which will be entrusted under the custody of Noir to accomplish their will. Silfilaru, a N’du worried of its people’s integrity, rejects the schemes of the witches and try to reason with Agnieszka in vain, which will drive him to try to murder her and puts him in exile.

Meanwhile, following the fall of Vilnia, and already having his position weakened, Jaroslav becomes more and more paranoid and decides to thin the ranks of the court, even sentences to a sadistic treatment the ambassadress of an allied nation who was close, despite herself, to find the secret of the lions. The queen feels that the situation slips out of her hands but struggles to impose herself in front of the voices that haunt the mind of Jaroslav, born from his excessive consumption of lions’ meat.

Now Agnieszka must attack the city of Rayrn where the witches feel that forces are underway. The night spirit allows the N’dus to attack more efficiently, protecting them from the light of the sun, mortal for them. The battle brings its share of deaths and leaves a bigger mark of fire and blood on Jaroslav's mind. Agnieszka has trouble understanding the motivations of the witches and their plans, and Noir orders her to go to them to bring back a mysterious artifact, the latter finally judging Noir trustworthy, or rather Agnieszka herself. However, to accomplish that, the Second must reveal herself entirely to the witches, by telling her story and the reasons behind her loyalty to Noir, reasons that she kept secret. This loyalty came from fear and anger, because she met Noir after she lost sight of her husband during a religious celebration and spent a night full of terrors, which made her hair turn white.

After that, the witches give her a feather, which in fact belongs to the lions kept in the castle and proves the very existence of those creatures. Agnieszka understands that she must fight against something beyond her and refuses to do so, because she doesn’t want to believe that she must face what the witches see as gods. Those same creatures end up making Jaroslav fall into madness, since he murders his mother when he discovers the truth about their utility and the role that he has on the balance of the kingdom. In the same time, he attacks the base camp of Noir, which he found thanks to the catch of the exiled Silfilaru. Agnieszka, in the middle of the slaughter, is captured by the soldiers; her only reward for having allowed the escape of her master and its allies.

Once in Jaroslav’s castle, Agnieszka is tortured but being kept alive by an enamoured champion since the battle of Vilnia, who decides to cut off her fingers as a precautionary measure. As she pretends to be relieved to escape Noir’s control, she will re-establish her bound with her unknown totem while trying to stay alive. The prince loses interest in her, judging her harmless, and throws himself body and soul into the exuberant preparation of a ritual supposed to bring back the lions and annihilate the darkness. At the end of an investigation right in the castle, Agnieszka understands that the lions will be present during the next big ball and that it will be the only occasion for her to reach them and to try to accomplish Noir’s will. But when she was supposed to take action during the festivities, as she is introduced by the side of Tomislav, Agnieszka goes back on her decision when she learns that Noir was captured while trying to lead an attack on the city. In the presence of a weakened Noir, Jaroslav gets the lions’ corpses and tries to accomplish his ritual, obviously in vain. As he is convinced by the voices of the lions that the ritual only needs more blood, he starts to slaughter the guests. As the evening falls more and more into violence, the champion manages to kill Noir, but is still sacrificed by the prince. Devastated by what she thinks is the death of Noir, Agnieszka manages to kill a lion and as she is about to die, she understands that Noir wasn’t a spirit or a corrupted human, but a snow cat, a very alive one, and that it is her totem. Noir can’t get past the fear of Agnieszka, who didn’t imagine Noir as her own shadow, her own anger and the manipulator of her thoughts to achieve its own goal of making the snow fall again. The snow cats being very powerful totems, Agnieszka was in fact always controlled by the witches who tried constantly to drive her into a corn and force her to agree with their desire to bring back the winter. She realizes rapidly that she must kill both the lion and the prince in order to have a chance of making the snow fall. But in the last moment, while the last lion is fading into dust, the prince attacks Noir and Agnieszka gets between them to protect it and is killed in its place. While winter is taking over the castle, and Jaroslav is dying too, the voices in his head finally fade away. Finally, the snow falls and the witches people rejoice, praising and despising Agnieszka, who never admitted her witch condition, for this miraculous fall, and they are ready to return to Morz again.

Noir, now a simple snow cat, and free from his dark trappings, is moving north, tormented by his actions and winter. It knows that he is followed. Actually, his will maintains Agnieszka alive, under the form of an animated corpse, fuelled by hatred, which protects Noir at any cost. During the night, she regains consciousness but doesn’t flee. She makes a promise to herself, to protect Noir until the end of time, even if she must slaughter all the witches to do so.