This gripping narrative revolves around a team of soldiers tasked with a potentially suicidal mission aimed at bringing an end to a devastating war. The film opens dramatically with Caroline Edh, portrayed by Noomi Rapace, caught in a mundane traffic jam alongside her daughter, Vanja (Stella Marcimain Klintberg). Their ordinary moment swiftly transforms into chaos as an attack occurs, leading to Vanja’s abduction.
Fast forward a few years, and Edh has transformed into a soldier on a train. Upon her arrival, she meets Lieutenant Nylund (Jakob Oftebro), who takes her to a military base. During their drive through a hostile area, he abandons her, but she bravely fights her way to safety. Once at the base, she attends a briefing led by Colonel Raad (David Dencik), where she meets fellow operatives including Granvik (Erik Enge), Karimi (Ardalan Esmaili), Malik (Dar Salim), and Captain Forsberg (Aliette Opheim). The stakes are high as they operate on the brink of disaster, with the enemy already dismantling military bases and threatening the HQ.
Their mission, named Operation Black Crab, involves crossing an ice-laden archipelago to deliver crucial packages to a research facility that could turn the tide of the war. During the briefing, Edh learns of a glimmer of hope—her daughter has reportedly been spotted in a refugee camp near their destination. This revelation ignites a fierce determination within Edh.
The team sets off on skates, but tragedy strikes when Forsberg falls through thin ice carrying the packages. In an instinctive act, Edh plunges into the freezing waters to help her, but she is forced to abandon Forsberg to save herself. Later, finding refuge in an abandoned house, tensions swell as Edh confronts Nylund about leadership after the death of Forsberg.
As danger looms, treachery arises when they suspect Karimi of betrayal. He denies wrongdoing, claiming he merely sought to contact his girlfriend stationed on a bombed-out base. The distrust escalates, but they decide not to kill him. As they evade enemy forces, they encounter a couple living on another island, leading to a violent skirmish that claims the life of Karimi.
The peril increases as Malik reveals that his wound is more severe than initially thought, and tragedy strikes again when he takes his own life rather than endanger the mission or spread a deadly virus discovered in a capsule. Driven by the hope of reuniting with Vanja, Edh pushes forward but soon finds herself in dire circumstances.
Struggling to keep her footing on treacherous ice, granvik and Nylund come to her aid. Nonetheless, their fight is far from over as they encounter enemy resistance, with Granvik heroically dispatching a gunner. Upon reaching a nearby camp, they are confronted by the horrifying aftermath of the conflict, revealing soldiers frozen in place.
Edh awakens to discover Nylund has absconded with the virus capsules, prompting a fierce confrontation. After taking a bullet, she manages to escape only to later confront an espionage-minded Nylund, who reveals his plan to discard the virus into the ocean, blocking Edh’s path to her daughter. In a fit of desperation, she shoots Nylund and steals the virus vials.
Rescued by horsemen, Edh soon finds herself in a hospital, only to learn from Commander Admiral Nordh (Susan Taslimi) that the earlier promise of seeing her daughter was a cruel deception. Enraged, she lashes out but is restrained. A chance meeting with Nylund reconfirms their mission—to eliminate the virus before it can devastate the world.
They successfully infiltrate a lab to secure the vials, preparing for a daring escape as alarms blare. In the chaos, Edh's injuries resurface, but she perseveres. As they make their way to helicopters, a final confrontation with the commander reveals the horrifying truth of their plans to weaponize the virus against humanity.
In a climactic act of defiance, Edh threatens to destroy the virus and, against all odds, chooses to leap to her demise, setting off the grenade amid the azure sky. The haunting final scene depicts her underwater, symbolically reunited with her daughter, while the reality of her sacrifice lingers as a poignant testament to her struggle and resilience.
