Captain Scarlet/Nightmare Fuel


 * Consider Captain Scarlet (either version, but especially the old one). In almost every episode, at least one person is killed so they can be replaced by a Mysteron "clone". Crushed in garage car-lifts (while cheery music (turned up loud, no less) plays from the garage radio), strangled with robot hands, brake lines cut. And then we see the dead body duplicated by the Mysterons. For true nightmare fuel, watch the end-credit sequences, where Captain Scarlet is subjected to ten different death-traps.
 * It gets worse when Fridge Brilliance kicks in-he still feels pain. Not only that, but he may never die, meaning he's doomed to watch everyone he ever cared about wither away, until he is alone.