When the initial Cylon attack against the Twelve Colonies fails to achieve complete extermination of human life as planned, twin Number Ones (Cavils) embedded on Galactica and Caprica must improvise…

Bellamy, Finn and Jasper head into Grounder territory to search for Octavia, as flashbacks show the siblings’ difficult childhood on the Ark. Meanwhile, Raven finds out about Clarke and Finn.

Tess forces Oliver to come to a Queen Industries gala to put the Board at ease, but things go awry when the Toyman shows up with a bomb and a…

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…

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

Amid a heated labor dispute, Tyrol asks the imprisoned Baltar for advice. Seelix becomes involved after she is turned down for flight training.