When Baltar's representatives face assassination attempts, Adama asks Lee to protect Baltar's lawyer. After taking on the assignment, Lee seeks to play an active role in Baltar's defense.

Baltar's trial testimony threatens the very stability of the fleet. Lee assists Romo Lampkin in Baltar's defense. Some in the fleet begin to feel that Baltar is divine. Though he dismisses such beliefs, Number Six suggests that the followers may know more about his true nature than Baltar does himself.

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.

With President Roslin missing along with the cylon base ship a new president must be decided on. Galactica goes on a search for the missing base ship and the Galactica crew members that were on board.

President Roslin faces off against Tom Zarek and Lt. Gaeta as they try to take control of the Colonial fleet. Both the alliance with the rebel Cylons and Adama's life are at stake.

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.