Battlestar Galactica is a 73-episode Anglo-Canadian-American science fiction television series developed by Ronald D. Moore, which aired on Sky One on October 18, 2004 and ended March 20, 2009 on the Sci-Fi Channel (now Syfy). This series is inspired by Galactica, another series created in 1978 by Glen A. Larson.
The Cylons, humanoid robots created by humans and become their enemies, have completely disappeared from the known universe after the signing of a truce about forty years ago. During this lull, humans have rebuilt their worlds (the twelve colonies), creating new ships and now live in some neglect of the past. The old Galactica battalion, which did well in the First Cylon War, is about to be demilitarized and turned into a museum. This is when the Cylons choose to reappear, equipped with new technologies that allow them to devastate the twelve human colonies by means of a generalized nuclear holocaust on the twelve planets. Protected from enemy computer viruses due to its obsolescence, only ancient Galactica can withstand the attack and thus becomes the only military escort of a disparate space fleet that gathers the last survivors of humanity. To give new hope, the refugee fleet then goes in search of a mythical thirteenth colony that would be called "Earth" as the Cylons set out in pursuit of them, determined to exterminate them.