The Demetrius and the Cylon baseship are nearly shot down by the Galactica when they rendezvous with the human fleet. Kara Thrace's team, however, manages to explain that the rebel Cylons want an alliance, not a battle.
Soon, the Cylon leader, a Six named Natalie, meets face-to-face with Laura Roslin and William Adama. She tells them that the final five Cylons are hidden in the human fleet, and that the D'Annas — the Cylon model whose consciousness was boxed as punishment for illicit spiritual exploration — can identify them. D'Anna's consciousness is stored within the Cylon resurrection hub, a central facility that controls all resurrection ships.
Natalie proposes that if the humans will help the rebel Cylons seize control of the hub and liberate the D'Anna model, D'Anna will identify the final five, who, in turn, can reveal the route to Earth. The hub will then be destroyed. All Cylons will lose the hope of resurrection, but Natalie's faction is willing to become mortal as the price they must pay to meet the remaining five Cylons. The rebels and the final five will then depart in peace, leaving the humans to complete their journey to Earth.
Roslin and Adama accept this momentous deal. Each side of the uneasy alliance, however, secretly plots to seize hostages during the mission in order to ensure that things go their way.
Tigh, Tyrol, Anders and Tory are shaken as they realize that their secret identities might soon be exposed. Anders is also preoccupied because Gaeta, whom he shot during the mutiny aboard the Demetrius, must have his leg amputated. The procedure leaves Gaeta desolate, singing to himself for consolation in the Galactica's infirmary.
Gaius Baltar, meanwhile, tells his radio audience a top-secret fact: Roslin shares inexplicable visions with two Cylons, Sharon Agathon and Caprica Six. In these visions, the three women pursue Hera, Sharon's daughter, through an opera house; Caprica always finds Hera first and carries her off, which frightens Sharon and Roslin.
Disgusted that Baltar has betrayed this confidential information, Roslin confronts Tory and reveals that she knows Tory and Baltar are lovers. Roslin demands that Tory find out how Baltar learned about the visions. Rattled, Tory persuades Baltar to admit that Caprica Six told him the secret, communicating through his lawyer.
The Quorum of 12, already uncomfortable with Roslin's reticence to discuss her visions, nearly revolts when Roslin summarily announces the alliance with the Cylons. Lee Adama privately urges Roslin to honor the Quorum's concerns by discussing the plan with them.
Accepting Lee's advice, Roslin and Natalie jointly address the Quorum. The political pressure appears to ease. Suddenly, however, the visions Roslin shares with Sharon and Caprica spark shocking real-life actions, threatening the alliance before the mission even gets underway.
Ascension, a three night event, premieres on December 15 at 9/8c
Get a sneak peek at the next episode of Z Nation, airing Friday at 10/9c on Syfy
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