All spoilers are unmarked. You Have Been Warned.
- The ending of "The Man Who Was Never Born"; Andro succeeds in averting the Bad Future, but at the expense of his own existence, leaving a despairing Noelle alone on a ship floating into outer space as the screen fades to black...
- The ending of "The Guests" offers another example of Star-Crossed Lovers separated by a Heroic Sacrifice. Trapped in a Victorian mansion that's controlled by an alien Brain Monster, Wade Norton and Tess Ames fall in love. However, they can't be together outside of the house; Time Stands Still inside it, so anyone who leaves reverts to their real age—and Tess has been there for too long to survive. When Wade declares that he's willing to stay in the mansion forever to be with Tess, she refuses to let him throw his life away—so she leaves the house, knowing she will die from Rapid Aging. Wade watches helplessly as she crumbles to dust. To add to the tragedy, the only reason Tess was in the house is that her father decided to "resign from the human race" by staying there and she agreed to remain with him because "he needed me".
- The ending of "The Architects of Fear", when Yvette realizes the monster dying in front of her is her husband Allen, whose life was pointlessly sacrificed as the result of a botched Genghis Gambit. To make it even more tragic, she's pregnant.
- The ending of "A Feasibility Study", where the entire town performs a Heroic Sacrifice together to save all humanity from being enslaved by aliens—and no one on Earth will ever know what happened to them, or why.
- A small, sad moment from "The Hundred Days of the Dragon". Vice-President Theodore Pearson confirms that President William Lyons Selby was not only assassinated and replaced by an Evil Doppelgänger as part of a conspiracy to take over America, but cremated and buried in an unmarked grave to prevent Identification by Dental Records. "He deserved so much more than that", Pearson says of his friend and colleague.
- The fate of the Limbo Being in "The Premonition", who is forever trapped in a Void Between the Worlds, is this as well as Nightmare Fuel.
- The ending of "Soldier". Just as it seems that Qarlo might adjust to the 20th century, The Enemy finds him in a violent, chaotic example of Diabolus ex Machina.
- The ending of "Demon With a Glass Hand". Trent learns that he's actually a robot and that his mission to save future Earth will prevent him from having anything resembling a normal life for at least 1,200 years. This shocks Consuela so much that she immediately abandons him.