As the scarred landscape still reverberates with the haunting remnants of a once-thriving civilization, a young woman named Anna navigates the devastated ruins of a nearby city alongside her brother, David. The vibrant metropolis now stands in disarray, a grim reminder of the horrific consequences brought on by a viral pandemic that unleashed waves of violence and feral behavior among its inhabitants.
After twenty-five long years of chaos, humanity's scattered remnants dot the landscape, and Anna and David's journey is steeped in a palpable sense of vulnerability as they scavenge for food and shelter in this unforgiving world. Their sense of dread amplifies when they spot a worn survivor approaching, compelling them to retreat deeper into the protective embrace of the woods.
As luck would have it, disaster strikes when David injures his ankle, leaving Anna with an agonizing dilemma: should she abandon her brother to safeguard their ailing mother? Despite David's desperate pleas, Anna tells their mother a comforting lie, claiming that David will return shortly from a hunting expedition. The following morning delivers an unforeseen tragedy as Anna learns that her mother has succumbed to time's unforgiving grip.
Amidst her harrowing navigation of this perilous landscape, Anna encounters another survivor named Peter, who introduces himself after gaining her trust. Sensing Anna's fierce independence and resourcefulness, Peter mentions his ties to a nearby religious commune. Observing the religious artifacts adorning her dwelling, he inquires about her faith, only to realize that she has a Christian upbringing.
As memories of her mother's last wish for her to find comfort among fellow survivors resurface, Anna begins to contemplate Peter's invitation to join the commune. The connection they forge while traversing the dangers of their environment lends Peter's proposition an alluring quality. Alongside their growing bond, Peter reveals the struggles of his past, explaining that he found refuge in the commune after experiencing abandonment or tragedy at the hands of his parents.
The journey towards the commune is not without peril, as the duo encounters scraggly individuals, including the sinister Berserkers – a faction of pagans who revere the plague and behave as if they remain tainted by it. These unnerving encounters serve to deepen Anna's feelings of dread and uncertainty about her surroundings.
As they draw closer to the commune, Peter cautions Anna about an old man by a campfire, warning that he might be responsible for the injury to his leg. However, curiosity gets the better of Anna, and she calls out to the old man. When they approach the fire, his son leaps from the shadows, disarming them. Frustration brews within Peter as Anna extends an invitation to these strangers, disregarding consultation—a decision loaded with troubling implications.
The old man's contempt for the commune exacerbates tensions, urging Anna to abandon her new friends. In a swift, brutal act, Peter retaliates, eliminating the men with a concealed knife, highlighting the danger they posed to Anna. As night falls, Anna finds herself caught in a web of conflicting desires for safety and her growing apprehension regarding the commune and its denizens.
Despite her initial hostility towards Peter's savage methods, Anna eventually relinquishes her weapons to the commune, only to uncover that a prisoner is about to face judgment. This prisoner is none other than the merciless pursuer who had previously hunted her and David through the perilous woods, prompting Anna to accuse him of causing her brother's fate. Tensions rise as Ben, the head of security, seeks to exonerate the prisoner, while Peter and Zack, the charming leader of the commune, advocate for his execution due to his perceived wrongdoings.
The unsettling revelation that Anna must undergo a baptism, viewed as a marriage ceremony by the other women in the commune, sends tremors of fear through her. Confiding her anxieties to Ben, she learns that dissent could brand her a heretic.
After enduring the baptism, Peter's advances become increasingly aggressive, culminating in an unsettling kiss. Zack insinuates that Anna's role in the commune involves procreating for the village elders, including himself and Peter. Alarmed, she attempts to flee, but Peter declares her God-given belonging to him. Just as the chaos escalates with the Berserkers mobilizing for an onslaught, Anna seizes a moment to escape, finding herself caught in the madness alongside David.
In a scene of horror, Anna witnesses David take Ben's life while a former prisoner-turned-Berserker attempts to extract revenge on him for betrayal. Despite Anna's intervention, David is steadfast, claiming that the Berserkers imparted crucial lessons on strength and survival. Disoriented by the whirlwind of events, Anna separates from David, only to find Peter once again. He disheartens her with the news that the commune has fallen, insisting on the need to foster a new community, envisioning Anna as his partner. This revelation ignites a severe confrontation, ultimately leading Anna to end Peter’s life, his last words of forgiveness lingering ominously.
Back at the fallen commune, Anna discovers that the only survivor is Judith, Zack’s wife, who had hidden away during the unspeakable tortures inflicted upon the others. Reflecting on their gruesome reality, Judith expresses her sorrow that the world has corrupted all it touches, to which Anna resolutely asserts that those involved have simply opted for immorality, their moral bearings forever shattered.
