Battlestar Galactica (1978)

S1E1 Saga of a Star World

The Cylon Empire deceives the Twelve Colonies, convincing them of their intentions for peace. However, they launch a surprise attack, decimating the unprepared colonies and obliterating the military's Battlestar fleet. The only remaining Battlestar, the Galactica, commanded by Commander Adama, rallies the surviving humans. Together, they embark on a quest to find the mythical 13th colony known as Earth.