A New Enemy

S1 E2: Going back in time to the 1950s, the Alien Explorers who visited Earth face the wrath of Siro'am. The Assassin lives up to her name in delivering their punishment. Returning to the present day, the alien attack force is being positioned. Meanwhile, back at the Pentagon... the Professor fills the team in on the imminent danger, using the appearance of a black hole as the harbinger of the alien atta