Captain of Cosmos (1979)

When a nuclear catastrophe lays an entire civilization, the Green Empire, to waste, its remaining inhabitants turn to the only method of survival they can think of: they take human beings into captivity and force them to rebuild their empire. Sent to rescue the captives are Captain Leo and his Cosmos Warriors. He strikes a deal with the Queen of the Green Empire, but when she refuses to let the captives go and orders the assassination of all the Cosmos Warriors, Captain Leo must prepare for a battle with much more at stake than just the well being of the captives. The fate of humanity just might rest in his hands.