President Roslin, close to death but still lucid and in command, orders Sharon‘s pregnancy terminated when a fetal blood sample is found to have unexplainable properties. Helo is outraged and Baltar dismayed, but Adama is determined to carry out the President’s final order—until it is discovered that the Cylon-human hybrid blood cells may have extraordinary healing abilities.

Meanwhile, an underground group of Cylon sympathizers, infiltrated by a copy of Number Six, turns violent and becomes an increasing threat to the Fleet.