The Battlestars Galactica and Pegasus face a new Cylon target, a "Resurrection" ship, while a power struggle threatens to result in all-out war among the human fleet.

The struggle between Adama and Cain is temporarily put on hold while the two Battlestars combine forces for an assault on the Cylon Resurrection Ship. Apollo faces a momentous decision and Baltar takes an interest in Gina, the Cylon prisoner.

Apollo assists in the search for a missing Raptor team as the new commander of the Pegasus grows increasingly unstable.

Tigh, Tyrol and Anders lead the Resistance on New Caprica to increasingly deadly attacks against the Cylons. Kara finds herself trapped in a new life with Leoben Conoy, and Duck makes a fateful decision. Meanwhile on Galactica, Adama struggles with the question of whether to return to New Caprica to mount a rescue attempt.

Adama plans to return to New Caprica and drop off a surprising person to act as a liaison between Galactica and the Resistance. Tigh's insistence on the use of suicide bombers and ever escalating violence stuns even the fellow leaders of the Resistance. Eventually, the suicide bombings cause the Cylon occupiers to crackdown on their human subjects.

Sharon helps the Resistance on New Caprica as Adama leads Galactica on a dangerous rescue operation. Tyrol races to save Cally from the execution squad. Meanwhile Anders uncovers treachery among the humans. Number Three meets the Oracle Selloi after having strange dreams about the temple.

The Colonial fleet faces starvation when the food-processing machines are contaminated. Kat plays a vital role in the success or failure of the "Passage" through space.

Tyrol discovers the Temple of Five on the algae planet. The temple may hold the Eye of Jupiter, which is believed to show the way to Earth. The Cylons take a keen interest in the discovery. Athena learns that her baby, Hera, may still be alive. Lee relies on Anders to help build civilian support for the protection of the Eye. His relationship with Kara complicates matters.

D'Anna/Number Three squares off against Adama over the Temple of the Five. Athena asks for Helo's aid in her plan to rescue Hera. On the algae planet, Apollo orders Dee to leave her defended position in order to save Kara. Anders helps Apollo to hold off the Cylon Centurion attack. Another copy of D'Anna finds the Temple and continues her search for the identities of the Final Five. Her messianic complex begins to concern the other Cylons.

As Baltar's trial comes to a conclusion, key members of the fleet discover that they may be the Final Five Cylons. Tigh attempts to decipher the strange music he is hearing in his head, while a Cylon fleet approaches.

President Roslin faces challenges as the Colonials plot with Cylon rebels to destroy a Resurrection Hub.

D'Anna holds President Roslin and other Colonials hostage in order to draw out the Final Five from the Colonial fleet. Col. Tigh believes he has the solution to end the standoff.

Kara struggles with the foreboding prediction of the Cylon Hybrid, while Adama and the Colonial fleet face despair over their shocking discovery.

Tigh and Number Six take their first glimpse at their unborn child, Tyrol offers Adama Cylon technology in return for his fellow Cylons properly reintegrated into the fleet, and an attempted coup leads to a costly struggle to maintain civility.

Loyalties are made clear when Gaeta orchestrates a coup d'état of the Adama regime. Both prisoners and lives are taken as many of the fed up people work to take over Galactica.

Ellen escapes from Cavil only to face a momentous choice regarding the 13th Tribe and the Final Five Cylons.

Kara feels lost while she struggles to cope with Sam's continued coma, meanwhile Boomer faces charges of treason from the Cylons onboard the base ship who blame her for voting against her model during the civil war causing the deaths of thousands of Cylons.

With Galactica on the verge of falling apart, Admiral Adama readies the ship for what could be its final mission, as Baltar's Six warns that humanity's final chapter is near.

Adama and the Galactica crew stake the survival of the human race on their plan to rescue Hera from the Cylon colony in this, the series finale.