Battlestar Galactica (1978)

Laurette Spang as Cassiopeia

The leaders of the Twelve Colonies of Mankind are making plans to sign a peace treaty with their mortal enemies, the Cylon Empire. On the eve of the ceremony, the Cylons betray the pact and destroy most of the Colonies and their entire fleet. Under the command of Commander Adama, the battlestar Galactica leads the remaining Colonial ships into space and seeks out a lost thirteenth colony, which turns out to be Earth. Along the way, the Colonials encounter various races (both friendly and hostile), the legendary human warrior Commander Cain, and the planet Kobol, the motherworld of all the Colonies. All the while, the Cylons – under the command of human traitor Count Baltar – closely pursue this fugitive fleet across the universe