Film Story :
The remaining vampire covens are on the verge of being wiped out by the Lycans. Both species are searching for Selene: the vampires seeking justice for the deaths of Viktor and Marcus, and the Lycans, led by Marius, intending to use her to locate Eve, whose blood holds the key to building an army of vampire-werewolf hybrids. Semira, a council member of the Eastern Coven, says she wants Selene to be granted clemency so that she can train the Eastern Coven's neophyte Death Dealers. To that end, Semira enlists Thomas to plead Selene's case before the full council. Thomas succeeds and Selene arrives at the Eastern Coven with David. Semira has her ally and lover Varga poison Selene, then slaughter the Death Dealers and blame Selene for it. Once Selene is under arrest, Semira begins draining her blood, which she intends to drink to gain Selene's power. Thomas and David try to rescue Selene, but they're attacked by Semira and Varga. They kill Thomas, but not before he's able to hold them off long enough for David and Selene to escape. The pair seeks refuge with the Nordic Coven. They are pursued by Alexia, an Eastern Coven vampire dispatched by Semira. Selene and David arrive at Vador, the stronghold of the Nordic Coven. Their Elder Vidar reveals that David was the son of the High Elder Amelia, making him the legitimate heir to the Eastern Coven. Alexia, who is secretly Marius's lover, tells Marius that Selene is going to the Nordic Coven. Marius and the Lycans attack the Nordic Coven. The Nordic vampires, led by Vidar's daughter Lena, fight with Selene and David. Selene engages in single combat with Marius, who demands to know Eve’s location. Selene insists she does not know the location, which Alexia confirms after tasting some of Selene's blood. Marius sounds the retreat for his troops and Selene, wishing to pass on to the sacred world, slides herself under the now-broken ice of the lake. Upon Alexia's return to the Eastern Coven's castle, she informs Semira of the events at the Nordic Coven. Semira kills her, revealing she knew of Alexia's treachery, and wanted Alexia to lead the Lycans to the Nordic Coven for her own ends. David returns to the Eastern Coven and presents himself as its rightful heir. Semira is arrested by none other than Varga, whose ultimate loyalty is to the rightful leadership of the coven. She is subsequently imprisoned in the dungeons. The coven comes under attack by Marius and his forces. The Lycans blow holes in the castle's walls, letting in sunlight, killing most of the vampires. David continues fighting, only to find himself face to face with Marius. Selene suddenly reappears, in a Nordic appearance and coat over her normal Death Dealer uniform. It is revealed that the Nordic Coven revived her through their passing to sacred world ritual and in doing so new abilities are enabled. She swiftly begins dispatching the Lycans, as the rest of the Nordic Coven, led by Lena, join the fight. While Selene is making her way through the castle, the guards in the dungeons are killed by Semira, who then escapes from her cell. Selene and David find Marius, but David is waylaid by Semira. As Marius and Selene's fight continues, a drop of Marius's blood lands on Selene's lips. She is suddenly flooded by a series of blood memories in which Marius finds Michael. She sees Marius capturing Michael and slitting his throat in order to collect his blood and consume it. Believing that Michael is dead, she bites her own wrist, using her own blood memories of the time she has spent with Michael, Eve, and David to fuel her rage. Although Marius has transformed, Selene rips out his spine, killing him instantly. David manages to kill Semira. He shows Marius's severed head to the Lycans, and forcefully tells them to retreat. In the aftermath, Selene, David, and Lena are chosen as the new Elders. It is revealed that after being resurrected at the Nordic Coven, Selene was reunited with Eve, who has been following her mother through their telepathic link.