- Anvilicious: If aliens looked at us and saw the Cold War, they'd wipe us out in self-defense. But if they looked and saw The Power of Love... they might let us live anyway. Of course, Some Anvils Need to Be Dropped though.
- Awesome Music: Arguably the best score ever written for a James Cameron movie, Alan Silvestri's stunning orchestra/synthesiser/choral music is widely considered among his best work.
- Dancing Bear: Possible example. See note on special effects.
- Jerkass Woobie: Lt. Coffey wasn't exactly a nice guy to begin with, hell, he even mocks Lindsay when she tries to inform the troops about High Pressure Nervous Syndrome, but there are times when it becomes clear how severe his condition is and he becomes a very pitiable man because of that.
- Karma Houdini: It could be argued that the aliens fall into this, as they (probably accidentally) cause the crew of the nuclear sub to die, and are never called on it
- Les Yay: One Night is driving one of the submersibles while the truck-driving song "Willing" plays on cassette. She starts singing along, and everyone else joins in over the intercom. She starts on the line "See my pretty Alice in every head light." Bonus points for playing a cover version sung by a woman, instead of the original which was sung by a man.
"THE CRANE! WE LOST THE CRANE! IT'S ON ITS WAY DOWN TO YOU!"
- Porting Disaster: The US and UK DVD releases are non-anamorphic. This means that on many TV/player combinations by default it displays in the correct aspect ratio, but with a huge black border around the whole picture. This is annoying if your system does not have a zoom feature.
- Older Than They Think: The role of Coffey would not be the first Ax-Crazy Big Bad role for actor Michael Biehn, as eight years earlier he played a Loony Fan of Lauren Bacall named Douglas Breen in the 1981 Slasher Movie The Fan.
- Squick: Coffey cutting rank chevrons into his arm with a K-Bar.
- Stop Helping Me!: When Lindsey is trying to get the rest of the crew to believe her about the underwater aliens, resident conspiracy nut Hippy goes into his usual Conspiracy Kitchen Sink speech. This results in a zinger:
"Hippy, do me a favor? Stay off my side."
- Strawman Has a Point: Coffey mutters, "It went straight for the warhead, and they think it's cute." In other words, just because it's not Russian doesn't mean it's safe, especially if said aliens have a Blue and Orange Morality.
- Visual Effects of Awesome: Dream Quest Images, Industrial Light and Magic (the pseudopod), Steve Johnson's XFX (the creature effects) and Fantasy II Film Effects (the climactic spire rising sequence), take a bow. And an Oscar.