The Cylons were created by man. They evolved. They rebelled.
40 years after the first Cylon War, the Cylons returned and laid waste to the Twelve Colonies. Gathering a ragtag fleet of civilian ships, the ageing Battlestar Galactica managed to escape the attack and set out to find the legendary home of the Thirteenth Tribe of Man - the planet known as Earth.
After months of relentless pursuit by Cylon forces, the Battlestar Galactica and the Colonial Fleet under her protection reunited with the Battlestar Pegasus, another survivor of the Cylon attack. Together they managed to strike back and destroy the Cylon Fleet's Resurrection Ship.