First Wave: Lungfish

After aliens create a great explosion, Will awakens to find that Don, Judy, Penny and Smith have been duplicated by the aliens, while the others have been put in a trance. The alien who has done this, Lemnoc, offers Will a deal: he can teach Lemnoc's aliens to act like humans or his family will be killed. He somehow frees everyone but Smith, who may have to be sacrificed for the others.