• Evil Is Sexy: Diana.
  • Fridge Horror: About Julie's past. During her brainwashing in the prisoner mothership, they use and amp up a memory from her past to begin the process. They say it happened when she was very young, it happened in an abandoned building, and it is her running away from what sounds like very heavy male breathing. Which then makes the whole Mind Rape thing rather more literal, even if not done directly.
  • Foe Yay: Diana and Mike Donovan. Especially seeing as they share a kiss when Diana uses hologram technology to pretend to be the mother of his son.
  • Moral Event Horizon: Daniel Bernstein steadily becomes worse as he joins the visitors, using his newfound power for petty acts of cruelty and to threaten other people to get what he wants. He eventually kills an old woman who was spying for the resistance in the Visitor Headquarters, despite her pleas to him to let her go and how she's known him since he was a kid. The moment is portrayed as the point of no return for him, and the resistance sets him up to be killed when they raid his house later on.
  • The Woobie: Willie was a minor part of the original miniseries and The Final Battle, but was so popular with fans they made him a regular on the subsequent television series. He's one of the first of the Visitors to join the Resistance, he speaks broken English ("English is not well to me. I learned Arabic for going there.") and at the end of Final Battle his human girlfriend dies in his arms after she takes a laser gun blast in the chest to save him. He's got a perpetual hangdog look and in the series he wears a bow tie!