- The exact nature of the crew of the Cygnus. Lobotomized by Reinhardt into mindless, subservient drones who can only continue to perform their tasks aboard the ship.
- It's even worse as it's implied the surgery to transform them into that was practiced with no anesthesia at all. The novelization lampshades this, Kate begging to be anesthesized as she lays on the operating table.
- The ending of the film with regard to the crew. The last we see of Reinhardt and Maximillian is Reinhardt's eyes darting madly to and fro from within Maximilian's visor, undeniably insane, as the new entity rules over the wreckage of the Cygnus, and its mindless, but entirely innocent crew in what looks to be a massive fiery cavern.
- The line graphs used to represent the titular space anomaly in the trailer and the opening, due to it looking so plain unnatural and being superimposed over the more terrifying moments of the film.
- Just the brief glimpse of the "humanoid-robot's" face when Durant removes the reflective faceplate; although still clearly alive, the crewman's face almost looks like a corpse, and the eyes seem on the verge of hemorrhaging. That little raspy breath he lets out upon being unmasked doesn't help, either.
- In the novelization is even worse. There, the eyes are replaced by seemingly cybernetic ones said to look like the faceplates they use.
- Maximillian, just by himself, is a perfect example. Between the whirly-blades, immunity to lasers, some lasers of his own, a single glowing red eye with a particularly intimidating furrowed shape, the menacing hum of the servos as he moves, and the way he just keeps coming while completely ignoring terrain, and eventually engulfs his own creator and presides over hell itself, how could you not have nightmares for years afterwards?
- Maximillian's execution of Durant, which prompts Reinhardt himself to beg for protection from his creation. (Although he might just be playing the sympathy card — he curses out Maximilian for killing Alex, but Alex had just found out Reinhardt's secret.)
- Dr. Reinhardt's pleas to Kate to protect him from Maximillian are another case of Nightmare Fuel should they be taken at face value, considering the possibility of spending decades practically all alone and having to look constantly over your shoulder to make sure your physically superior Dragon isn't trying to kill you.
- What makes this all the more unsettling is that the movie was produced by Disney!
- The heroes desperately fleeing across a flimsy gantry that's dwarfed by the huge fiery meteor that's rolling towards it.
- In the novel, the very final moments of Reinhardt after the falling viewscreen traps him with the Cygnus being torn apart by the black hole's gravity, its lobotomized crew ignoring his pleas for help, Maximilian gone, and watching how both the ship is approaching to the hole and how the surviving Palomino's crew is able to escape just before dying of explosive decompression when the control tower is torn off.
Nightmare Fuel / The Black Hole
As a Moments subpage, all spoilers are unmarked. You have been warned.