So we have created a new arm of the law: the Grammaton Cleric, whose sole task it is to seek out and eradicate the true source of man's inhumanity to man: his ability to feel. — Father
Badass Longcoat: Preston himself, and the Clerics in general.
Although Preston is the only one we see doing any actual Gun Kata: Partridge is deliberately letting Preston do all the work, Brandt's only on-screen shooting is with an assault rifle, and none of the other Clerics bother.
Bodyguarding A Badass: In the final fight, Brandt guards DuPont even though it is clear after Preston cuts off Brandt's face that DuPont is a master at Gun Kata.
Boomerang Bigot: DuPont wants to destroy all sense-offenders, despite the fact that he is one himself.
Boring Invincible Hero: Preston. The director finds it boring when the villain "gets a few good licks in" on the hero because he has no intention of subverting audience expectations with a Bad Guy Wins ending, and thus, there's no point in making it seem like the villain has an advantage at all when the result is a foregone conclusion. He does acknowledge that not everyone likes this approach.
Broken Faceplate: Invoked when Preston shoots a couple mooks in the face, with no visible blood.
Bullet Proof Human Shield: At one point, Brandt machine-guns a sense offender who is grappling with Preston without killing him too.
Chekhov's Gun: Where Preston literally hands his gun to Brandt for later exploitation.
Church Militant: Despite serving a secular state, the Grammaton Clerics use the trappings of this trope.
Some of the quasi-religious vibes are a bit more subtle: Though it also sort of resembles the Nazi swastika, the symbol of the Librian regime is most similar to the type of cross seen on the coat of arms of the medieval Kingdom of Jerusalem.
That, or it resembles the "decapitated cross" of Brave New World. This is a drugged-out dystopia, after all.
Faceless Goons: The Sweepers, who wear either riot gear or storm-coats, but almost always wear closed helmets.
First Time Feeling: Hits Preston hard, not least because, at the time, he's found and is listening to an old vinyl album of Beethoven's Ninth Symphony, one of the most tremendously moving pieces of music ever produced by the human species. Even the script describes this introduction to human emotion as 'unfair'. (But it does a lot to explain his subsequent actions.)
Flat What: The reaction of the Nethers captain to seeing two of his men killed with their own shotguns.
Foreshadowing: Two instances. First, DuPont is teaching the Gun Kata class early on because he himself is a master practitioner. Second, in the beginning of the film, Brandt comments that he needs to stop by an Equilibrium center to have his dose adjusted, meaning he's either under-medicated or over-medicated.
John's daughter playing with her cereal near the beginning of the film foreshadows that she is no longer on Librium.
As does the fact that his son gets annoyed with her hint that he isn't on it either.
Idiot Ball. The Big Bad lets Preston, the highly trained Cleric who has killed multiple Faceless Goons and proven himself a serious threat, walk into the main headquarters without even bothering to search him for weaponry. He then tells Preston the master plan and as soon as his villainous monologue ends, Preston pulls out some firearms and fights his way to the boss's room. In a deleted scene, it would've shown earlier that the metal detectors are at the next door Preston walks through after taking the lie-detector, which raises the question of why they put the anti-gun security measure there instead of before the room they planned to spring their trap in.
It Is Pronounced Tropay: Preston absolutely murders the pronunciation of Ludwig Van Beethoven.
I suppose if his elite guard are also feeling, it might be a security measure designed so that Brandt has an advantage with his pistols if any try to turn on him.
Kick the Dog: The Sweepers are shown gunning down fleeing and captured Resistance members, and dogs.
Late Arrival Spoiler: "Not without incident." The trailer doesn't provide enough context for it to be a real spoiler, but you'll know where it's coming in the movie, and it was clearly intended to be unexpected.
Meaningful Echo: Near the end, DuPont echoes the Yeats poem Partridge was reading near the beginning: "You're treading on my dreams."
Before shooting Partridge, Preston mentions the anger and hatred felt by sense offenders. Partridge replies, "A heavy cost. I pay it gladly." When DuPont asks Preston whether killing a feeling human is worth the price, guess how Preston replies?
When Preston starts following Partridge's path, he repeats some of his excuses. "They miss things, sometimes..."
Mobstacle Course: Preston does this at least twice, one time without a real purpose besides just wanting to be alone.
Mondegreen: When Preston doubts the wisdom of overthrowing the government, he says "What about war, the everyday cruelties that are all gone now?" Jurgen's response is, "Replaced by the Tetragrammaton?" Many think he's saying, "Replaced by a touch of grammaton?"
My God, What Have I Done?: When Preston rewatches the recording of his wife's incineration, this time being able to feel. His face becomes a mask of complete and utter horror when he sees how he had just stood then, uncaring and cold, while she had been sent to a gruesome fiery death.
Earlier than that, the first time he kills a man after he goes off Librium.
Never Trust a Trailer: The trailers make it seem like Preston's wife was arrested recently and his motivation is pure revenge.
Pistol Whipping: The scene where Preston tries to let the sense-offenders escape.
Plot Hole: Supposedly, Preston swapped his government-issued (and personalized) gun with Brandt's to frame him for killing the Sweeper patrol. The swapping scene clearly happens after the killing scene, and in any case he used two guns in the fight and only swapped one. Some people think this hole is obvious and unforgivable. Others forgive it in order to enjoy the rest of the film. Still others come up with bizarre, elaborate justifications for why it makes sense if you think about it hard enough. The actual explanation is that the narrative was shuffled in editing to improve the pacing, and the director decided to let the plot hole slide.
This troper thinks that an earlier scene where Preston gives Brant one pistol, before picking up another, could be when the swap occured.
Same Story, Different Names: Writer-director Kurt Wimmer's follow-up project Ultraviolet rehashed most of the basic elements of this film. William Fichtner even appears in both.
Polygraph Operator: "How would you say would be the easiest way to take a weapon away from a Grammaton Cleric?"
Brandt: "You ask him for it."
The Stoic: After starting as one, Preston quickly turns Not So Stoic as he struggles with having and hiding emotions. He even suffers a Heroic BSOD, but becomes The Stoic again before the final battle.
Straw Hypocrite: DuPont and Brandt aren't on Prozium. In the commentary, the director explains that this was done because most people assume that breaking their own laws is one thing all tyrants have in common, and he cast Taye Diggs as Brandt partly because of his giant smile.
Straw Vulcan: The ideological mainstream is so set in the belief that emotion is at the core of "man's inhumanity to man" that any attempt to evoke feelings in oneself or others is punishable by summary execution.
Take That: The way items are rated, banned, and destroyed is a dig at the MPAA rating system.
Tear Off Your Face: Preston kills Brandt by slicing his face off with a katana.
There Is No Kill Like Overkill: Pretty much the philosophy driving the movie. Aside from the overkill in combat, you really don't need dual flamethrowers to destroy a single painting.
Unorthodox Reload: Preston has some sort of device up his sleeves (literally) that will reload his pistols for him when they run empty.
During the final shootout, Preston is confronted by a hallway of machine-gun Mooks. He throws two magazines of ammunition halfway down the hallway, then starts shooting, running out of ammo exactly where he dropped the two magazines, reloads and continues gunning 'em down.
And the one guy assuming his Walther WA 2000 is a shotgun, racking a nonexistent pump.
Father extolls Prozium as the "opiate of the masses", a frequent variation on Karl Marx's view of religion as the "opium of the people".
Window Pain: Done repeatedly with Sweepers' visors. You'd think they'd be made of something that didn't spectacularly shatter at the slightest impact.
Writing Around Trademarks: In the finished film, the emotion-deadening drug is called "Prozium"; in at least some drafts of the script, it was instead named "Librium".