Accidental Aesop: Tolkien's anti-war message conflicts rather badly to modern readers with Eowyn's position as an amazingly progressive Action Girl for the time, giving the impression that her ending up happily hanging up her sword is saying that women should Stay in the Kitchen. It does not help that she is the only one to explicitly do so.
The Orcs, helped by the fact that Tolkien was worried about the implications of the Always Chaotic Evil trope (that he detested) and apparently intended for them to be Proud Warrior Race Guys serving Sauron only because of his power over them. He would have introduced this part of them and expanded their role in future editions too, except...
Who was the real hero - Sam or Frodo? Word of God favored Sam.
Applicability: Tolkien discussed this in the foreword to a later edition. He pointed out that a lot of the things people insisted were allegories of World War II (e.g. the Ring as the A-Bomb) were conceived of before the 40s and any similarity people find is due to hindsight, as well as detailing what the story would have been if he had actually written a WWII allegory. He disclaimed allegory and used the word applicability instead - allegory is an intention of the author, but applicability is free for the reader to determine.
Award Snub: Issac Asimov thought so, at least. When his own Foundation trilogy got the special Hugo Award for "Best Series," he stated that he thought Lord of the Rings deserved it more.
Early on in The Fellowship of the Ring, Tolkien briefly stops the action to describe a fox's train of thought, which runs something like this: "three hobbits, out at this hour, beneath a tree? I sense a disturbance in the fox." Tolkien concludes with: "and he was absolutely right, though he never found out any more about it."
For those who have never read any other Tolkien, Tom Bombadil is this. They visit him and he doesn't play any other real role afterwards. The only impact this has on the story is to explain where Merry gets the sword he uses when fighting the Witch King of Angmar.
Whether one likes Tom Bombadil and his whole episode or not.
Denethor, opinions vary as whether he was a pitiable character or a total Jerkass who deserved what he got. It doesn't help that he was less fleshed out in the movies and made into somewhat of a villain rather than a Asshole Victim.
Whether the many songs and poems in the books are any good or not.
Whether the books are better than the movies or vice versa.
Some consider the end to be too long. Hence the whole subplot of the "Scouring of the Shire", taking place after Sauron is defeated, was dropped in the movies. Yet Tolkien wasn't eager to pawn off a pat "happy-ever-after" ending. Instead, the heroes' homecoming is just as important a part of the journey as it was in the old epics it emulates.
Did you know that if we had the internet in the 1950s, that people would probably be describing this as the same way they do to popular 21st century whipping boys like Twilight and Inheritance Cycle? The Lord of the Rings didn't catch on until the 1960s.
Peter S. Beagle expressed it well in the foreword: "The '60s[...] were when the word progress lost its ancient holiness, and escape stopped being comically obscene."
Die for Our Ship: Poor, poor Arwen. Aragorn/Boromir, Aragorn/Legolas and Éowyn/Aragorn fans hate and bash her like there's no tomorrow. The fact that she was a late addition (Tolkien didn't create her until the third draft) really doesn't help her any, and her love story with Aragorn is in the appendices.
Many fans are grumpy about anyone spelling his surname "Tolkein" or pronouncing it "Tol-kin", "Tol-kyen" or "Tolky-yen" rather than "Tol-Keen". And even spelling "Middle-earth" as "Middle-Earth" in extreme cases.
When Galadriel gives gifts to the members of the Fellowship, most of them get some pretty cool items Sam, on the other hand gets a box of dirt, leaving the reader to ask, "Is the box of dirt going to help?"
The lighthouse imagery of the Eye of Sauron gets stronger throughout the books, up to and including a red beam sweeping over the Hobbits as they climb Mount Doom. Then come the movies, and the Eye of Sauron as a giant evil lighthouse become very literal.
"At that moment there was a knock on the door, and Sam came in. He ran to Frodo and took his left hand, awkwardly and shyly. He stroked it gently and then he blushed and turned hastily away."
Legolas and Gimli get their fair share, too.
When King Elessar gave up his life Legolas followed at last the desire of his heart and sailed over Sea. We have heard that Legolas took Gimli Glóin's son because of their great friendship, greater than any that has been between Elf and Dwarf. If this is true, then it is strange indeed: that a Dwarf should be willing to leave Middle-earth for any love, or that the Eldar should receive him, or that the Lords of the West should permit it.
The Entwives, who lived in what is now the Brown Lands, after a campaign by Sauron. Extends to the whole Ent race, because without the other sex, there will be no new Ents. (Word of God confirms that the Ents did "die out" after a fashion - the ones that weren't killed by something basically turned into trees.)
Iron Woobie: Frodo is the definitive example of this trope.
It Was His Sled: Boromir dies. Gandalf comes back. The Ring is destroyed. Aragorn gets crowned King of Gondor. Though arguably the last of these was heavily forshadowed in the poem about him early in the story, and the third is almost a given in a story like this.
Gollum, in a Jekyll/Hyde split personality example: the Sméagol persona is a sniveling Woobie, while Gollum (his desire for the Ring given form) is pure Ax-Crazy Jerkass.
Less of a Jerkass or a Woobie than Gollum, but still qualifying, is Boromir. He has several bad ideas (and be fair, some good ones) on how to conduct the quest and never quite understands that the Ring cannot be used for good until he actually tries to steal it. However, he has more immediate fears for his homeland than anyone else, as he's actually been on the front lines against Mordor and knows that his homeland will fall if there isn't some major intervention, so it's not surprising that the Ring finds him a willing listener.
Magnificent Bastard: Sauron. Especially after reading the appendixes and learning about everything he did to set up his victory - not to mention his role in The Downfall of Númenor. Or at least, he tries to be one, but he's playing far out of his league.
Mainstream Obscurity: The book is a humongous bestseller (often ranking as second bestselling novel of all time) and practically revered in the Fantasy fandom for being a trendsetter, but for the general audience, it's best known through the film versions (and videogames).
"Frodo Lives!" and "Gandalf for President," both popular rallying cries from The '60s.
"Tolkien is Hobbit-forming." Also, anything having to do with Hobbits.
Political discourse: "Frodo failed, X has the ring" or "Y is like the One Ring, everyone wants it"... Strangely influential, perhaps because many poli-sci geeks see the Ring as an allegory for nuclear weapons or the corruption of tyranny.
"Another piece of Mordor," often seen scrawled on ugly building projects under construction.
"One does not simply X." Usually on top of a photo of Boromir saying the original line. note A slight case of Beam Me Up, Scotty! since the hand gesture of the meme actually accompanies the line "The Great Eye is ever watchful", which he says immediately afterward.
It was this series that popularized the entire concept of telling a story in three parts. Ironically, Tolkien intended it to be published as one work and hated that he had to split it up.
The same goes for those who consider it an allegory for Christianity; Tolkien similarly Jossed the idea that Gandalf's death and rebirth as Gandalf the White was supposed to invoke Jesus. This is borne out by the rest of the mythos, where it's revealed that Gandalf's "race"note for lack of a better term is basically a lesser Angel, and Tolkien did consider having the God figure appear as a mortal to drive out evil but ultimately discarded the idea.
Even the One Ring itself gets this. Way too many people have used replicas of this symbol of evil as wedding rings.
The book has a strong following among white supremacists.
Burzum, which is an example of the previous two points (the band's name itself is in Black Speech and Varg Vikernes is well-known for his white supremacist ideas).
Éowyn settling down with Faramir does NOT equal to her either "just settling for second best" or becoming a boring housewife. Her and Faramir's relationship is a part of An Aesop of the book that peace, healing and nurturing are better than war and violence (especially when the war is over) with language evoking a Call to Agriculture. Éowyn befriends and eventually falls for a man who helps her realize that she was more of a Death Seeker than anything else, so ultimately she chooses life over death, and falls for someone who even as a Forest Ranger ordered his men never to kill without need. Also, becoming a ruling lady of a princedom is different from becoming a housewife: it's a very tough position. The fandom, and specially fangirls, insists that Eówyn was chickified and "reduced" to a Trophy Wife or a House Wife. Ironically for modern readers, shieldmaidens in actual Norse sagas hung up their weapons whenever they married ("maiden" refers to being an unmarried woman), so Éowyn is perfectly in line with her legendary forbears.
Moral Event Horizon: With all the evil that Saruman does, it's instructing his orcs to start denuding Fangorn forest in order to fuel his forges that causes him to cross it. As Treebeard says, ''A wizard should know better!" Ultimately, it's also what brings about Saruman's downfall.
Narm: Some lines in the book come off as rather narmy, like "praise them with great praise" and "their joy was like swords".
Orcs and Balrogs - you'll find them in many generic fantasy settings alongside mythological creatures, but The Lord of the Rings is the first (published) work to use them. "Orc" is an Anglicized Elvish word ("Orch" in Sindarin, which gives the wonderfully apropos plural "Yrch"), while Balrog is Sindarin for "powerful demon."
The word "orc" actually existed in Old English, but it was a vague term for an ogre or a demon. Same goes for "ent", which was a generic term for a giant (the related word "eoten" is a cognate for the Norse "jotunn", all referring to giants). It was only after LOTR that they started being used to refer to very specific fantasy creatures.
Nightmare Fuel: Some of the scenes involving the Nazgûl are pants-shittingly terrifying, as well as the general feeling of panic and being hunted while the hobbits are escaping the Shire. Also, Sauron.
The idea of a ring that makes you invisible goes back to the Ring of Gyges from Plato's Republic. Considering how well-read Tolkien was, it's probably where he got the idea in the first place.
Prior to the popularization of the Middle-earth books, the term "elf" usually made people think of little people, such as how they're portrayed in Rudolph the Red-Nosed Reindeer and various other works. There was usually little difference in most peoples' mind between elves and fairies, or other sprites. Imagining them as tall, beautiful beings is usually credited to Tolkien, but the first known usage of this type of elf was in Lord Dunsany's The King of Elfland's Daughter. Since these writings, however, all fantasy elves are presented this way.
One-Scene Wonder: The Balrog is easily as famous as the other monsters from the books despite only appearing very briefly.
Only the Author Can Save Them Now: At the climax on Mount Doom, Frodo has ultimately fallen to The Corruption and will not choose to throw the ring into the cracks. So Gollum has to try for the Ring and fall in himself, taking the Ring with him. In this case, the trope fits in with the previously-established themes of the book: No one could resist the Ring's corruption long enough to complete the quest, mirroring the fact that man cannot save himself without the aid of divine grace, and the event that ultimately saved the Quest resulted from an apparently independent choice made earlier (Bilbo's pity).
Ron the Death Eater: Poor, poor Arwen. Boromir, Denethor, and Thranduil definitely tend to get this treatment in fan fiction.
Seinfeld Is Unfunny: A slew of imitators followed in Tolkien's wake, some more blatant than others. Still other writers used Tolkien homages, and almost every fantasy-based game has used Tolkien-esque elves, dwarves, Orcs, etc. Then there's Dragon Lance and Forgotten Realms, which draw heavily from the sort of worlds that Tolkien created. Add to that the number of times other writers are compared to Tolkien that by the time a reader gets to the Real Thing, they've seen it before...
The Fellowship of the Ring: Gandalf vs. the Balrog.
The Two Towers: Shelob (moved to the third movie).
The Return of the King: Mount Doom.
Slow Paced Beginning: It takes around half of The Fellowship of the Ring to properly start the quest of the Ring.
They Wasted a Perfectly Good Plot: The faceoff between Gandalf and the Witch-King beneath the broken gate of Minas Tirith has all the makings of a truly EPIC showdown...and then the cavalry arrives (literally). The way it plays out is still awesome, but many a reader has wondered how that battle would have gone if it hadn't been interrupted.
Some of the concepts may not go over well with some readers: the idea of inborn royal status and special fate, the general fact that most of the heroes are aristocracy, and the uncriticized use of monarchy as a positive form of government. Of course, as Word of God says, the book was not intended to be an allegory about "how things should be done" in the real world - it's a fantasy inspired by medieval legends and history, where people certainly didn't think like modern people do. (Plus some of the most heroic individuals - namely Sam and Beregond - were emphatically not aristocratic. Beregond didn't even have a rank beyond man-at-arms.)
Particularly of the above, Sam frequently calls Frodo "Master". Even though this was the usual way for a servant to refer to his employer, this may feel off to modern audiences (like today's Americans) living in a time and place where class distinctions have been downplayed. The movies thus downplay it too by having him stick to "Mister" instead, which is deferential without being servile.
Tolkien seemed to think it was acceptable (under some circumstances) for platonic same-sex friends to hug, kiss, sleep together, and express deep love for each other. Modern readers commonly disagree.
Vindicated by History: The book wasn't really popular until the Vietnam War and then the reading public started seeing parallels between Vietnam and the War of the Ring.
Just as the only evil in Lothlorien is evil that the visitor brings there, the only symbolism in Lord of the Rings is symbolism that the reader brings there. See Tolkien's quote under What Do You Mean, It's Not Political?.
Some critics have tried to find Christian symbolism in it (similar to C. S. Lewis's The Chronicles of Narnia, which is more openly Christian), with Frodo, Gandalf and/or Aragorn being classified as Messianic Archetypes, Boromir's death by arrows evoking St. Sebastian's martyrdom, or some such other connection. It is true that Tolkien was a devout Catholic, yet the only symbolism he admitted to was the Elven "energy bread" lembas being reminiscent of the Christian Eucharist or Holy Communion.
There are many, MANY interpretations of the book as a thinly veiled allegory of World War II. In particular, according to this view, Sauron is A Nazi by Any Other Name, and the whole Scouring of the Shire episode is a satire on Communism. Tolkien started to shoot down these interpretations when he was still alive, but when has Word of God ever stopped fans (or not-fans)?
"I cordially dislike allegory in all its manifestations, and always have done since I grew old and wary enough to detect its presence." -Tolkien, responding to this in a forward to a later edition.
Tolkien's old buddy CS Lewis adored allegory, hence his Narnia books being nothing but allegory. They had such a falling out over allegory in Narnia (and other things Lewis did that pissed Tolkien off) that Tolkien and Lewis didn't speak for awhile. They agreed to disagree and got over it, buddies again, but it must have really rankled Tolkien to the end of his days when people saw allegory in The Lord of the Rings.
The first complete Russian translation of Lot R, and still one of the best known, ran with the "Scouring as a parody of communism" idea by translating Lotho's titles as those once used by Stalin.
The Ring is a force of great power that is alluring to men, but cannot be controlled even if its power is harnessed and will twist you into a monster before it kills you. This is in no way a metaphor for nuclear power and weapons or radiation poisoning, the Ring's powers are completely literal.
Tolkien stated that if the books were an allegory of World War II, the Ring would have been used against Sauron at once, and Saruman would have made his own, turning the war into an Evil vs. Evil situation in which whatever side was victorious would have wiped out the hobbits.
The Woobie: Faramir. For one, his father says straight out that he would have preferred that Faramir die. Then he essentially tells Faramir to go try and die anyway. This isn't as pronounced in the books as it is in the film, mind - Faramir pretty much goads his father into putting it in so many words (and their relationship wasn't nearly so antagonistic until the very last draft).
Ralph Bakshi Animated Film
Broken Base: Either you'll hate the film or you will be intrigued by what Ralph Bakshi made.
Cult Classic: Following tradition with Bakshi's work, this film has gained a cult following after being released on home video.
Ho Yay: If you thought the Jackson films made Frodo and Sam look gay...
Narm: Hey, Samwise, what do you think about your portrayal in this adaptation?
They Just Didn't Care: Despite the rich languages that Tolkien invented, and the number of people fluent in them even back in 1978 (as much as you can be fluent in them), composer Leonard Rosenman used made-up gibberish for the soundtrack's choral chants, with the occasional word like "Sauron" or "Mordor" thrown in.
Rankin-Bass Animated Film
Anvilicious: In case you miss the deeper meaning in any particular part of the movie, there's usually a song to explain it to you. Or two. Or three. See the page quote for a good example.
Ass Pull: Éowyn appears out of nowhere with no prior set up to bump off the Witch-King and then vanishes completely with only a brief appearance at the end.
Designated Hero: Aragorn. Apparently he was just off doing his own thing with nothing to do with the rest of the party, and doesn't even help in the Siege of Gondor as the Orcs were already retreating by the time he arrived. He's rude to Gandalf, sneering at him while taunting him over his reluctance to march on Mordor, a move motivated not to buy time for Frodo but because he thinks they have Sauron on the run. And despite doing nothing to help, almost getting his army killed and being a rude prick, he's still celebrated as the savior at the end. Very different from the more heroic Peter Jackson version, to be sure.
The orcs' Villain Song "Where There's a Whip, There's a Way" features the lyrics "We don't want to go to war today, but the lord of the land says nay nay nay!" Thirty-five years later, the rapper Silentó gave us the hit single "Watch Me (Whip/Nae Nae)."
Ho Yay: Some. But with Frodo and Samwise, can you expect anything less?
"BEHOLD! THE GARDENS OF MY DELIGHT!!"Aww...Dark Lord Samwise is so cute. Samwise's blackest desires of despotic tyranny involve turning the Plains of Gorgoroth into a lush garden paradise and Sauron's army of orcs into raccoons and tropical birds. Hardly the stuff to crush Middle Earth beneath his Hobbit-sized heel... which is the point - Samwise very much isn't Dark Lord material, and that's a major reason why he can resist the Ring's temptations.
The relationship between Frodo and Sam is subject to Ho Yay interpretations just like in the books.
And just like with the books, fans debate whether Frodo was the real hero of the book or if the real hero was actually Sam, since Sam was able to resist the ring's influence despite being in close proximity to it as opposed to Frodo, who eventually did become corrupted by it, if only temporarily, after carrying it for so long.
Big Lipped Alligator Moment: The Watcher In The Water. It shows up, attacks the Fellowship, gets shot in the face with an arrow, destroys the entrance to Moria behind them and then it's never even given a passing mention afterwards.
Can't Unhear It: Sean Astin's distinctive accent for Samwise Gamgee is very similar to one of the most famous (extant) audio narrations of the book, though Astin claims he wasn't aware of the audio version. Eerily, Sam is never actually written with such an accent in the books, making it all the weirder. Another amusing tidbit is that the audio actor, Bill Nighy, is physically about the least Hobbit-like actor imaginable.
Crazy Awesome: Viggo Mortensen. During the filming of Helm's Deep, he caught a sword in the face, and broke a tooth. He wanted to Superglue the tooth back and keep filming, but Peter Jackson brought him to his dentist to fix it instead. All of the other actors were afraid he was going to end up killing himself before they finished filming, due to his insistence on performing lots of extremely dangerous stunts himself. Even the stuntmen were impressed by his dedication, and ability to ignore pain and injuries while filming.
Howard Shore's score is usually recognized as one of the best in film history, sometimes even by people who weren't fans of the movies. The three Academy Awards (two for best score and one for best song) didn't hurt this either.
Lux Aeterna's song, "Requiem for a Dream," which was present in the trailer of The Two Towers. In the early days of Youtube (circa 2005-2007), it was used in damn near every fan-made video and rivaled Linkin Park for AMV soundtracks.
Ear Worm: The Green Dragon song from The Return of the King has this effect.
Common complaint of the end of the third movie. It doesn't help that the screen fades out in about five places and really looks as though the film is ending there, only for it to reappear again. Slightly different cinematography may have made this a much less common complaint.
Discussed on the cast commentary track, where somebody says that the fade after "Here, at the end of all things" could be the end of the movie, albeit a very artsy and far-out ending.
Inverted for some fans of the original books, who actually claimed that the ending was too short due to the Scouring of the Shire being turned into a vision that Galdriel gives to Frodo in the first film.
Genius Bonus: A little bit of extra awesome for those versed in The Silmarillion. In the scene in the extended edition where Sam tells Frodo, "There's light and beauty up there that no shadow can touch," the star he sees is no ordinary star. That's the Star of Eärendil, the Evenstar - yeah, the one Arwen was named after. We would call it Venus. In Middle-Earth, though, it's an elf (Arwen's grandfather, no less,) on a flying ship with one of the three Silmarils, which contain the light of the Two Trees; holy light that predates the sun and moon. The Star of Eärendil was the source of the light contained in Galadriel's Phial.
Genre Turning Point: Along with the Harry Potter series, the LOTR trilogy proved that fantasy films didn't have to belong to cheesy B-movie fare and could be critically and commercially successful. A literal torrent of high-budget, CGI-heavy fantasy, sci-fi and superhero blockbusters followed in the next few years, and there seems to be no end to it.
In the 1950s, Tolkien was contacted by producers who wanted to make an animated adaptation (unconnected to Ralph Bakshi's effort, which happened after his death). He was sent a draft script to review. His response, included in The Letters of J.R.R. Tolkien (#210), was filled with complaints that sound a lot like the ones some fans would make about the live-action trilogy, including "a preference for fights."
On the flip side, Tolkien was willing to accept changes if the financial benefits were satisfying enough - as he put it (letter #202): "Art or Cash: Either very profitable terms indeed; or absolute author's veto on objectionable features or alterations". While he greatly objected to some aspects, such as beaks and feathers on the Orcs, he actually suggested some changes that would be more acceptable. So he wasn't as unyielding as some fans can be.
Legolas riding the Uruk-hai shield like a surfboard in The Two Towers becomes a lot funnier when you learn that Tolkien originally intended for Bilbo to kill Smaug in the earliest drafts of The Hobbit. How? Bilbo would have infiltrated Smaug's lair, then stabbed him through the bare spot in his chest with Sting (which went so deep it vanished completely), and then ride a golden bowl like a surfboard on the massive amount of blood pouring out of Smaug's belly before triumphantly exiting the mountain.
Frodo and Sam, as usual. Actor Ian McKellen, who is gay, was interested in the close relationship between the two characters. He noted the attention to detail in the pair's close relationship from page to screen, such as when Sam grabs Frodo's hand after he awakens from unconsciousness. In fact, both pairs of hobbits can reasonably be called Heterosexual Life-Partners. It's worth noting that Sam is ironically the only hobbit to show interest in any specific woman in the films. In this regard, Merry and Pippin might be closer to this trope than Frodo and Sam. This is pushed Up to Eleven in the DVD cast commentaries for the three films (but especially The Two Towers), where all four hobbit actors play with this trope at one point or another.
The cast commentary even provided some for the actors. Sir Ian rather comes off as if he has a little crush on Elijah Wood. Everyone else sounds like they've got a crush on Sir Ian.
Aragorn/Legolas also get a lot of this. Actually, Aragorn/anyone do. Viggo kind of encourages it.
It really doesn't help that some scenes with just Aragorn and Legolas together (like after the battle of Helm's Deep) were originally supposed to be romantic scenes of Aragorn and Arwen.
And not only Legolas. Viggo kissed Billy Boyd offscreen. Really
"Instead of a Dark Lord, you would have a queen, not dark but beautiful and terrible as the dawn! Treacherous as the sea, stronger than the foundations of the earth! All shall love me and despair!"
"Po-Ta-Toes! Boil 'em, mash 'em, stick 'em in a stew..."
"Stupid fat hobbit! You ruins it!"
"You have no power here" is a popular macro, complete with senile Théoden's laughing face.
"Share the load."
Pretty much everything Gollum said, particularly in The Two Towers where he got his first time to shine. "My preciousss..."
"I have no memory of this place" has become a popular expression for anyone who attempts to make an account for a website and is told they already have one.
"We been eatin' nothing but maggoty bread for THREE STINKIN' DAYS!"
"LOOKS LIKE MEAT'S BACK ON THE MENU, BOYS!"
Misaimed Fandom: A lot of fans cheer for Eowyn because, unlike Arwen, she's a Badass Princess who gets a lot ofaction and fighting, while Arwen does no fighting and her arc mainly revolves around her love for Aragorn. Modern fans tend to miss that Tolkien chose to write strong heroines who's dreams are portrayed as equally valid to one another, as well as that Arwen's choice is a difficult one and entirely her own and no less right than Eowyn's choice to fight (and they sometimes forget Eowyn retires from war once it's over and happily settles with Faramir).
Galadriel's rant when she is tempted by the Ring. For some, Nightmare Fuel of the High Octane variety. For others it can be cringeworthy. Galadriel on a whole can come off this way. The actress is attempting ethereal and somewhat inhuman... it can easily come off as if she's just really really stoned and looking at Frodo like an extra-large bag of Cheetos.
The heck was with Denethor running a whole mile while on fire just so he can go over the edge?
Certain lines, especially "Let's hunt some Orc", "Nobody tosses a dwarf!" and the all-too-obvious title drops. Not to mention how Jackson worked in some rather ham-fisted allusions to the book's chapter titles. "It was only a detour. A shortcut!" "A shortcut to what?" "Mushrooms!"
Gimli's reaction to seeing Balin's tomb. In the book, he merely puts a hood over his face. In the movie, he sobs like a wino for what seems like several minutes.
"Crebain from Dunland!" It Makes Sense in Context, but since that context isn't elaborated on in the film, it just seems like a really weird way for Legolas to yell "Uh oh, birds!"
Sauron's depiction as a literal flaming eye on top of Barad-dûr. In the book, Sauron was stated to still be a humanoid, and "Eye of Sauron" was just a metaphor for his power; Peter Jackson's decision to basically turn Sauron into a big, scary lighthouse has been met with some derision. The Hobbit films seem to address this by indicating that Sauron's humanoid form is actually contained within the eye's pupil.
"Fell voices on the wind", or Christopher Lee singing in the shower?
The Orc runner who carries the torch to set of the charges that breach Helm's Deep. For one thing he's completely shirtless and running down a trench of cheering, roaring Orcs. It'd be like some kind of twisted version of the Olympics if it weren't so ridiculous.
The Extended Edition reveals that the Dead Men's first answer to Aragorn's summons was an avalanche of skulls. Apparently they had been piling them up for just such an occasion??
Sam being inspired to go back to save Frodo by finding the lembas bread Gollum had thrown off the mountain. It's like he was somehow convinced that he really did eat it.
Pippin's line "We are sitting on a field of victory," due to the huge hunk of bread in his mouth combining with his Scottish accent to make it sound like he's saying "We are shitting," which actually kind of fits the situation too. Rifftrax notably completely ran with this.
Many lines were perfectly fine originally, but have become Narm due to Memetic Mutation. One does not simply walk into Narm Charm.
"THEY'RE TAKING THE HOBBITS TO ISENGARD!"
This is a bit of an odd one as the line was perfectly fine in the book, but then the film failed to make clear that there was some question of whether the orcs were going to Isengard or Mordor, making it seem like just another one of Legolas' Captain Obvious moments.
Just about every bonding scene between the hobbits, Frodo and Sam, rely on the film earning audience respect for them beforehand.
Boromir's anguished rant at no one in particular in Fellowship of the Ring, punctuated by falling into a pile of leaves. In any other film, utterly ridiculous. But Boromir's Tragic Hero status and Sean Bean's acting sell the hell out of it, and it's a near-Tear Jerker.
Sméagol turning into Gollum at the beginning of Return of the King.
Shelob. If you are an arachnophobe at all, you will have nightmares for a good while. Peter Jackson himself is and made sure to use that.
The Jump Scare in Rivendell where Bilbo abruptly turns Gollum-esque and lunges for the ring.
Never Live It Down: While more of a Base Breaker than a scrappy, Frodo is often accused and criticized for doin' nothing but get his ass saved from the trouble he's in and abusing poor Sam. Many, however, tend to forget that he chose to bear the weight of the One Ring which is physically and mentally wearing him down throughout the entire trilogy, and that said "abuse" is due to the Ring warping his mind. The results would no doubt be the same if another person were to take up the task.
Billy Boyd is actually the oldest of the four main Hobbit actors, and was in his early 30s when the films were made.
For the record, Elijah Wood was the youngest of the four hobbit actors (he was the youngest member of the entire cast, in fact). In the books, Frodo is the oldest of the four hobbits and Pippin is the youngest.
Figwit, aka "Frodo Is Great... Who Is That?", a random elf that got a sudden fanbase.
Sauron in his physical form in the prologue.
The Mouth of Sauron in the Return of the King Extended Edition.
The Easterlings in the Two Towers. In an army comprised mostly of ragged orcs, these highly disciplined, heavily armored human warriors marching to aid Sauron would certainly stand out. Unfortunately after the scene of them marching into Mordor they are never seen again.
The Scrappy: Denethor from The Return of the King, who is viewed in this movie as a complete crazy jerk instead of a complex, sympathetic, Shakespearean Anti-Villain, gets a lot of hate due to his Jerkass behavior.
Signature Line: Gandalf's "YOOOOOOUU! SHAAAALL NOT! PAAAAAAAASS!" is arguably the most remembered and most often quoted line out of the trilogy. Even if he only said it a couple times in one scene in the first movie.
These start to pop up to the trained eye after repeated viewings.
In the aerial shot where the ring is destroyed and the ground under the orcs surrounding the good guys is collapsing, the dust is obviously swirling on a plate behind the little CGI orcs, as it doesn't pass in front of them.
The montage of the Minas Tirth warning beacons being lit. Yes, it's a climactic moment in the film and the music and sweeping landscapes were breathtaking, but the fire effects were on the whole poorly done, with the Minas Tirith and Amon Din beacons being engulfed within five seconds with an obvious flame superimposed over the wood stacks, which just as obviously aren't burning at all. Plus, most of the montage has beacons alighting atop the very narrow peaks of towering, snow-covered and wind-blasted mountains (a task that would redefine being Reassigned to Antarctica), with nobody shown to be lighting them even in shots where the beacon is close enough to the screen where such details should be seen.
In fight scenes, it's quite common for people being "stabbed" to actually have the sword tucked under their arm, which is one of, if not the oldest tricks in the moviemaking book. It's always in the background of shots, but once you start to notice...
When Aragorn and Frodo are on the Collapsing Stairs of Khazad-Dum, it is...rather obvious that they are in front of a green screen, with a fan blowing at their hair. (Understandably, since they couldn't possibly be filmed on a collapsing 500-ton staircase...) This was a very rare case of a failure that was quite easily visible on first viewing.
Another obvious green screen: when Saruman descends the stairs at Orthanc the first time he's seen.
Not so much "special effects failure" as much as "director didn't catch it when filming" but in the scene in the first film when Aragorn runs to the dying Boromir (It's the next wide shot after he kills Lurtz, specifically) pay attention to the Uruk-Hai corpses. One of the extras raises his head to look around after Viggo moves past him.
When Legolas tries to shoot the torch bearing Orc during the battle of Helms Deep he is shooting his normal green and brown arrows but the arrows that connect are the white ones of Lorien.
When the Fellowship is running from the Orc army in Moria, there is a scene just after their escape from Balin's Mausoleum where the tiny, running figures are clearly CGI characters rather than the actors themselves. If you look at them, rather than the Orcs gathering around them, you can see their legs aren't bending as they run, and their heads are swiveling evenly, as if they were all made of Lego.
In the final movie, as Frodo is hanging over the edge in Mount Doom, Frodo's "missing finger" is just done by him bending his index finger to hide the rest of it from the camera. Occasionally it doesn't quite line up and the rest of his supposedly bit-off finger is clearly noticable, most notably when he grabs Sam's hand.
Some of the methods used to depict the height differences between the main characters are more easily noticeable than others. In particular the very cheap method of rarely showing their faces at the same time, so you see Elijah wood and the back of a seven foot tall scale double dressed as Gandalf; then the camera cuts to a different angle and you see Ian Mckellen talking to a four foot tall scale double dressed as Frodo. Once it's pointed out to you that the character with their back to the camera isn't the same person who plays them when facing the camera, it becomes very hard not to notice the wigs and body proportion differences between cuts.
Notably lessened as allusions to Aragorn's inherently kingly status and confidence (almost magical, as mythology was wont to do) are greatly reduced in the movie, to the point his major character arc is reversed to personal reluctance to be king.
It's still present in Gandalf's speech to Pippin in Return of the King, where he is given lines that were spoken by Denethor in throes of madness in the book no less, how the rule being given to "lesser people" caused Gondor fall to to ruin.
At the Battle of Helm's Deep, Théoden sends the women and children to hide in the caves... well, roughly half the children, at any rate. All boys able to bear a sword are torn from their mothers' arms and forcibly conscripted for what is sure to be a suicide mission. At the opposite end of the spectrum, very elderly and feeble men are also drafted, per Théoden's orders, and one of them starts the battle early when, unable to hold his bow steady, he accidentally shoots an Uruk Hai warrior. Unsurprisingly, the boys and old men are slaughtered, while the able-bodied women of soldiering age, who, though also untrained, would at least stand a better chance of not being instantly killed, cower in the caves, completely unutilized. Aside from the fact that most modern audiences associate child soldiers with tyrants like General Butt Naked and Joseph Kony, were it not for the assistance of the Elven reinforcements and the eleventh hour arrival of Gandalf with Éomer and the Rohirrim, every last person at Helm's Deep would have been killed. And, with a niece like Éowyn, it's not like the idea of a sword-wielding woman is completely alien to him.
Frodo in Return of the King when he ends up not listening to Sam and trusting the psychopathic Gollum instead.
Also in Return of the King, after Gandalf knocks out Denethor after yelling, "Abandon your posts!", why does nobody (including Pippin, who is the only person to figure out that Faramir was just knocked out from poison) take advantage of Denthor being knocked unconscious and get Faramir to the House of Healings or get him medicine and have him recover?! If they did, they would've saved his life and he wouldn't almost be burned to death without regaining consciousness!
The Woobie: Frodo. Perhaps overly so, as a common criticism of the character (or at least Elijah Wood's portrayal thereof) is how he spends basically the entire trilogy with a pained expression on his face.
WTH, Casting Agency?: Some older LotR fans objected to Elijah Wood being cast as Frodo, as they believed that he looked too childlike. However, it can be justified, as the book specifically points out that the Ring (which he acquired just as he came of age) stopped Frodo's aging.
BBC Radio Adaptation
Flat Joy: When Faramir asks the people of Gondor whether they will accept Aragorn as king, the book's "And the people cried out yea with one voice" sounds like a dull "Yay" in the radio version. The crowd's "Praise them! With great praise!" also comes out pretty flat.