Nine members of the fellowship, nine black riders, nine rings... and nine fingers on Frodo's hands when he finishes his journey. Sauron also has nine fingers after the one with the ring gets cut off. In the end, everything bows to symbolism.
After reading the Silmarillion, suddenly the whole sequence with Shelob, already horrifying, becomes both a hundred times more intense and very symmetrical. The draining, total darkness in Shelob's lair isn't an absence of light, but Shelob is quite literally excreting darkness as its own material, just like her mother Ungoliant. Also, the light of Eärendil, which is the light of a Silmaril, shines through that darkness. When Ungoliant devoured the first trees, Fëanor refused to allow the use of the Silmarils to restore them. At one point, Tolkien was considering adding a chapter to The Silmarillion in which Eärendil kills Ungoliant, which would have made "Shelob's Lair" even more symbolic.
Galadriel giving Gimli three locks of her hair. Once you read through the Unfinished Tales and read about the description of her hair and how the Eldar believed that the light of the Two Trees were ensnared in it and how Fëanor was attracted to it, yet she refused to give him any lock. Some of the Eldar believed that her hair inspired Fëanor to create the Silmarils. So it was a very great honor that she gave Gimli not one, but three locks of her hair. It sort of mirrors her Character Development: she starts off a prideful Noldorin princess, setting out to forge her own land in Beleriand. By the end of the Third Age, she is mature and wise enough to not only turn down the Ring, but graciously gift something as trivial as a lock of hair (or three) to a traditional enemy of the Eldar. Seems plausible that she wanted to mend relations between the Dwarves and Elves, partly because she saw how King Thingol's pride was his downfall in regards to the Dwarves.
Aragorn's alias Thorongil is a combination of his father's — Arathorn - and his mother's — Gilraen – names.
Sauron was actually right about the Ring — no one could have destroyed it!note Gandalf even suggests that not even Sauron himself could pull his will together to do it, even as he had the means and knowledge. All those eagles visions would fail, as no one would throw the Ring into fire. Sauron didn't even need to protect the cracks — even Frodo, who was specifically suited to be least affected by the ring, was incapable of destroying it. It took several twists of fate and coincidences, also known as Eru ex Machina, to destroy the One Ring — something that could not be predicted by Sauron.
Denethor's madness wasn't just because of Faramir's injury and the Palantír's visions of the power of Mordor. The Palantír also showed him things that caused him to believe Frodo had been captured and Sauron had obtained the ring. Specifically, if one checks the Tales of Years, Denethor saw Frodo captured in Cirith Ungol, which happened the day before the Siege of Minas Tirith.
"Comfort me not with wizards!" said Denethor. "The fool's hope has failed. The Enemy has found it, and now his power waxes; he sees our very thoughts, and all we do is ruinous."
When the Fellowship are in Lothlórien, it's said that Aragorn left the hill of Cerin Amroth and "came there never again as a living man". This seems strangely specific, but still merely a fancy way of saying he just didn't go there again, until you read about Arwen's death, when she "laid herself to rest upon Cerin Amroth." It's possible (even implied?) that Aragorn did return — in spirit, already on the higher plane and indeed not as a living man; to wait for Arwen so they could go wherever next together. Subtle reunion or what — but it makes their story all the more poignant.
Gollum's fall into Mount Doom wasn't an accident.
Earlier, when Frodo orders him with the power of the Ring, his exact words are: "Begone, and trouble me no more! If you touch me ever again, you shall be cast yourself into the Fire of Doom." Gollum touches Frodo again — and guess what happens. So in a way, Frodo did cast the Ring down himself — if not in a way that he, and likely Gandalf, intended.
Even earlier, Frodo told Gollum:
"You will never get it back. At the last need, Sméagol, I should put on the Precious; and the Precious mastered you long ago. If I, wearing it, were to command you, you would obey, even if it were to leap from a precipice or cast yourself into the fire. And such would be my command."
So Gollum's fall into the Cracks of Doom was his obeying a command that Frodo (who still had the Ring on his finger, even if the finger wasn't attached) had given to Gollum some time back — to leap from a precipice and cast himself into the fire.
Later than that, when Gollum attacks the duo in Mordor, Frodo tells him that if he touches the Ring again, he will be "cast into the fire". And that's exactly what happens. Effectively, Frodo uses the Ring to curse Gollum, in order to prevent his regaining it. And ultimately, that means that the malice of the Ring was its own undoing.
This is also the one time that Frodo uses the Ring's true power. Invisibility and long life are side-effects (Sauron didn't need either power when he made the Ring). The real power of the Ring is to command. Perhaps this was the moment that Frodo crossed the line, making himself unable to throw the Ring away when the time came.
Gollum's fall into Mount Doom serves as a fitting character arc for him. On one hand, he's an intensely tragic character who does show some hints at redemption and loyalty towards Frodo. At the same time, his obsession and corruption from the Ring are central to his character and he can't simply redeem himself due to its irrevocable damage. Thus, his final fall manages to fulfill both purposes; his reuniting with the ring manages to satisfy his base desire, while his inadvertent sacrifice to destroy the ring maintains at least some form of redemption. Gollum "possessing" the ring in any other fashion would've clashed with Frodo's wishes.
As you read the series, you come to realise that almost all the good races have at least one twisted, corrupted counterpart — Orcs, if you go with the published version of the Silmarillion, are Elves ruined by Morgoth, or at any rate were made in envy and mockery of the Elves; the Nazgûl are the evil counterparts of men, Trolls those of Ents, the Balrog is an evil Maia and therefore the ruined counterpart of Gandalf, and Gollum is a corrupted Hobbit. Dwarves are the only race that, on screen at least, don't have an evil counterpart. Which makes sense considering that, according to the Silmarillion, dwarves were made sturdy and difficult/impossible to corrupt by Aule. (Men with Rings became Nazguls. Dwarves with rings became greedier and more distrustful.)
The Sackville-Baggins' pretensions towards respectability and their political ambition are symbolised in their name: "Sackville" is partly "Baggins" translated into French (Fr. "sac"= Eng. "bag"), and with the suffix "-ville" (Fr. "ville" = Eng. = "town"), it implies that instead of Hobbiton, they want to live in Bagginstown. No wonder one of them gets himself elected mayor.
The Rings of Power are pretty much the embodiment of Be Careful What You Wish For: they latch onto the primal racial desires of their Bearers, give them the means to achieve them, then give them an all-too-appropriate downside. This is also the reason Gandalf feared the One Ring so much he won't even touch it: as a Maia, wielding greater power than any Elf or Man ruler and the innate sense of superiority of a god, he (or Saruman as well) might have turned into a tyrant just as great as Sauron if the Ring dominated him.
Mortal Men desire temporal power and long life. The Mortal Ringbearers are turned into the Nazgûl. They are deathless and immensely powerful, but they are basically ghosts in the thrall of Sauron: devoid of any real physical form, personality, or will of their own.
Dwarves are miners, craftsmen, and merchants. The Dwarven Rings bring their Bearers great wealth and renown. They also bring their Bearers unchecked greed and paranoia, hostility with other races, and ultimately ruinous warfare with Orcs and Northmen.
Elves want simply for things to continue as they are, unchanged. The Elvish Ringbearers are the leaders of the last three great Elven kingdoms in Middle-Earth, and are able to maintain their realms in peace and relative safety from the outside world. However these realms are little more than havens, little bubbles of Elvish culture in a changing world... and the Ringbearers can't do much outside of those bubbles. They have become isolated, withdrawn, and unable to affect the world at large. For the most part they don't even leave their realms; they simply live in the past, unable to deal with the present.
And Hobbits just want to be left in peace, unnoticed, invisible.
At first, Gandalf comes across as simply the prototypical grumpy old wizard. But upon a closer reading, you understand the real genuine reasons behind his grumpiness: he's the only wizard left who's actually doing his job. Of the five Istari, one turned evil, one went native, and the other two just wandered off somewhere. Gandalf is doing the job of five people all by himself. He's traveling far and wide, perhaps even the entire length and breadth of Middle-Earth, gathering information, rallying the Free Peoples, dispelling evil... and he's doing it all while constrained in the body of a wizened old man. No wonder he's cranky. He's got no time for your silly little Hobbit nonsense; he's trying to save the world here!
When Frodo, Sam and Gollum are crossing the Dead Marshes a Black Rider flies overhead, around the hills and back to Mordor. A few days later when they reach the black gate another one flies over them, but this time it keeps going... to fly over the rest of the fellowship after Pippin looks into the Palantír that evening. The Black Gate is northwest of Barad-dûr, and further northwest is Isengard.
It seems kind of silly that Tolkien made the One Ring's power invisibility, considering it's toted as a power great enough to rule all of Middle Earth, but the professor was actually referencing Plato's logical questioning of morality in The Republic, the parable of the Ring of Gyges. The One Ring acts as the ultimate temptation to do whatever you want, so it is the ultimate test of one's morality! Gollum used the Ring for evil, since it helped him steal and kill whatever he wanted. Bilbo used the Ring to aid his friends and fulfill his quest, but later used it for more selfish purposes like avoiding nasty relatives and eventually had to give it up for the sake of his own sanity. Frodo went out of his way to avoid using it, and only ever used it by accident or under duress. Sam only ever used it once to save Frodo and then easily gave it up once Frodo was rescued.
It makes some sense that the One Ring's default set of powers were invisibility and long life. The greatest threat to the Ring isn't being found by an Elf or Maia...such a powerful being would eventually be twisted into challenging Sauron, so it'd get back to Sauron that way. Its greatest threat is ending up in the hands of a nobody who'd never use it to command anybody, so Sauron would have no way to find it. Invisibility and long life are two things most mortals would want, but they're also two powers that people would eventually talk about...just like Hobbiton is talking about Bilbo at the beginning of LOTR. That way, all the Nazgul have to do to find the Ring is ask around about rumors about unusually old people with a tendency to vanish into thin air.
In the Houses of Healing Pippin says of Aragorn, "Was there ever anyone like him? Except Gandalf, of course. I think they must be related." Aragorn is a descendant of Lúthien, and so of Melian the Maia, so in a way they are related.
When Elrond warns Gimli against taking an oath to fulfill their quest he isn't just speaking in general but from experience. He knows someone who was broken by their oath, his foster-father Maglor.
One common Headscratcher is "Why didn't the Eagles just take the ring to Mordor?" According to one theory, Gandalf secretly planned on taking the fellowship to where the eagles live and having the eagles fly them to Mordor. The eagles lived on the other side of the Misty Mountains but all the routes for crossing them were too dangerous and difficult, and Gandalf (along with his secret plan) ends up falling down a chasm in a battle with the Balrog. Just before falling with the Balrog he tries to surreptitiously tell them the secret plan ("Fly, you fools!") but was too surreptitious and they didn't understand. When he came back as Gandalf the White he had forgotten many things, including everything from his name to the plan to meet the eagles.
In Cirith Ungol, Sam is talking about the old stories and Galadriel's light and suddenly realizes that with the phial, Eärendil's story is still going on and they're just in a new part of it. Well, Eärendil's light is from a Silmaril. A Silmaril's light is from the Two Trees of Valinor. In other words, Sam and Frodo are using the light of the Valar themselves to fight Shelob and break the Watchers' invisible gate. (As to why it fails later, a cup of the stuff, as powerful as it is, still isn't enough to overcome the ocean's worth of Sauron's darkness when they're on his doorstep.)
Orlando Bloom's performance is rather stiff, but he becomes much more expressive whenever Legolas is speaking Elvish. So it might be that Legolas himself is inexpressive because he's not very comfortable speaking Westron. (Elves are known to be very insular, and Elrond and Arwen might be better at Westron because they're leaders and expected to have contact with the outside world. Meanwhile, Galadriel is magic.)
In The Two Towers, there's a scene where Saruman is preparing explosives. Wormtongue is curious (he's never heard of explosives before), and leans over, and Saruman looks at him funny. It looks like Saruman was implying "You're an idiot for not knowing what explosives are." But Wormtongue is holding a candle, and if he had leaned just a little bit farther over, it would've really changed the plot of the movie. This also doubles as a great moment reinforcing the "practical wizard" aspect: although it might look like magic to the natives, Saruman isn't just waving a wand around and repeating mumbo jumbo, he's using real intellect. It helps sell to the audience that there might be similar principles behind other things they can do, and ironically that it's NOT simply a case of A Wizard Did It.
There's a whole layer of depth to Merry and Pippin's story arc that you don't realise first time around.
Up until the moment where Gandalf separates them, they are practically attached at the hip, with Merry always looking after Pippin (nearly ten years Merry's junior). When they are separated, Merry finds a new close friend in Éowyn and Pippin does the same with Faramir. Pippin ends up looking out for Faramir and even risking his own life to save him, by getting up on the pyre. Meanwhile, Merry lets Éowyn take care of him (even stated in dialogue — "Whatever happens, stay with me. I'll look after you.") After the Battle of Pelennor they are reunited, and it is now Pippin who looks after Merry.
Boromir dies to save Merry and Pippin (and actually does save them, since that orc seemed intent on hacking them to pieces when Boromir showed up). The Hobbits are later freed from the uruk-hai thanks to Éomer attacking. Pippin goes on to save Faramir's life and Merry to save Éowyn's. Faramir and Éowyn then fall in love. Thanks to Boromir and Éomer aiding the Hobbits, their siblings survived the war and ended up married.
Éowyn and Merry are developmentally the same age; she is 23 and Merry is 37, (since hobbits' life cycles are about twice as long as that of humans); meanwhile Faramir and Pippin are both, in a sense, little brothers.
While the charge of the Rohirrim has is one of the most epic movie moments ever, a lot of people thought it was slightly deflated by the ridiculous reaction shot of the stunned Orc commander. He couldn't really believe that three volleys of arrow fire would turn back the charge, could he? But from his position at the bottom of the hill, he couldn't see the vastness of the Rohirrim army. He couldn't imagine that Rohan could field a much larger force than the one Gondor sent to attempt to retake Osgiliath, which he had easily slaughtered. For Rohan to commit so many troops to the battle, they would have to leave their own lands undefended for the benefit of an ally, a risk that he couldn't imagine taking. So he's stunned not just by the fearlessness of the charge, but by the fact that so many Rohirrim are there at all!
The scene near the start where Bilbo drops the Ring is one that is very, very unsettling. Something's not right, but you can't quite put your finger on it. Later, usually on another watching, you finally realize what it is: It does not bounce. It simply falls and stops. It's a fantastic underscore to the fact that the Ring is very unnatural. The effect incidentally was created by using a very strong magnet under the floor. It's meant to express the Ring's symbolic weight, both in importance to the Middle-Earth's fate and as a burden on Bilbo's, and later Frodo's shoulders. In The Return of the King, you can actually see scars on Frodo's neck, caused by chafing of the chain due to the Ring's heaviness. Specifically, it starts getting much heavier once Sam and Frodo have passed Sauron's tower and are continuing on towards Mount Doom. The burden of carrying the Ring isn't just growing because Frodo's had it for so long, it's because the Ring is trying to protect itself by hindering their travel. This might even resolve the Lava is Boiling Kool-Aid effect when Gollum falls into the Cracks at the end: while Gollum should be lighter than lava and not sink into it, the Ring is forcing him under with its unnatural weight, desperate to delay its own destruction for a few more seconds.
At first the impact of the ring on Frodo seems rather extreme, but aside from Bilbo (who only handles it before Sauron's rise to power), and Gollum (and look what happened to him), Frodo is the only one to ever touch the ring. Everyone else just comes close to touching it, then pulls away or is forced away somehow. Well, except for Sam. He carried/wore it while Frodo was being held prisoner in the tower. Of course the only time he actually touched it was when he held it in his hand while confronting the Orc. He'd also shown himself resilient to the Ring when he resistsbecoming "Samwise the Strong" with a "garden of his delights", and he didn't carry it for very long anyway.
There's European folklore explaining you have to kill a wizard three times to keep him dead. Interestingly, Saruman in the movie is stabbed with a knife, falls from a great height, and gets impaled on a spike. Naturally, an actor famous for playing Dracula gets impaled right in the chest...
When Gandalf shows up at Mt. Doom, there are three eagles. The first, ridden by Gandalf, grabs Frodo. The second grabs Sam. Why the extra eagle? Just in case Sméagol had been redeemed by Frodo. Gandalf sees many possibilities.
Why, when Frodo offered Galadriel the One Ring, did she mention about becoming "beautiful and terrible as the dawn"? What's terrible about dawn?
Ask a Troll that same question... With Galadriel as a Dark Queen, all the Races of Middle-Earth may come to feel the same way a Troll feels about the morning rays. According to the backstory in The Silmarillion, Galadriel was older than the Sun, and actually saw what the first sunrise did. The light of the sun transforms everything that it touches — everything. The fact that it's nice happy sunlight doesn't lessen the impact.
This is probably also a case of the way characters in Middle Earth speak in archaic language. The original use of the word "terrible" meant awe-inspiring, begetting a feeling of insignificance and/or terror in those who see it. Being an amazing spectacle of nature, dawn can indeed be quite "terrible."
The flag of Rohan is a white horse upon a field of green with the sun shining behind it. What happens at the end of the Two Towers? Gandalf, riding a white horse, leads the cavalry charge of the green-cloaked Rohirrim to Théoden's aid, with the sun rising behind them. Also happens in Return of the King, with Théoden, riding Snowmane, leads a mass of green cloaks with the sun rising behind them (albeit from the wrong direction).
In the film of The Two Towers, Aragorn begs Théoden to ask Gondor for aid, and he retorts, "Where was Gondor when the Westfold fell? Where was Gondor when our enemies closed in around us? Where was Gon..." and then cuts himself off. The end of that sentence, the part he couldn't bring himself to say, was, "...when my son died."
The Throw It In of Gandalf's hitting his head on a ceiling beam in Bag End was a happy accident that managed to achieve three things:
It was funny.
It reinforced the size difference between humans and hobbits by showing that humans don't fit comfortably into spaces designed for hobbits.
It suggested that Gandalf is not all-knowing and that he can be taken by surprise. Thus, it's all the more believable that he is completely blindsided by Saruman's betrayal and that he doesn't see it coming when the seemingly defeated Balrog uses his whip to pull Gandalf off the Bridge of Khazad-dûm.
What happens to Gollum upon falling into the lava of Mount Doom is surprising: He doesn't die right away and doesn't even seem to notice the excruciatingly hot lava that engulfs and slowly kills him. It makes sense, however, if the Ring's bestowing of "unnatural long life" to Gollum not only extended his years but also made him extremely difficult to kill. That would also explain how he survived what should have been a fatal fall outside Shelob's Lair; and it makes Gollum's death a foreshadowing of the Ring's own similarly slow death by lava.
When watching Cate Blanchette's performance as Galadriel, something seems very odd about her. Her movements, mannerisms, and even how she speaks all seem off somehow (for example, her conversation with Frodo when he looks into her mirror). Something is also different about her eyes in the scene in which she greets the Fellowship, and a closer look reveals that she's the only character in the scene whose eye shine is made up of a globe of dozens of individual points of light. Everyone else's eyes (even Celeborn's) reflects a single point (this was a conscious decision by the video effects team). Then you remember: Aside from Gandalf and Saruman (and of course, Sauron), Galadriel is the only character we see in the films who has been to Valinor (she was born there), and it's made clear in the books that Elves who came out of the West are literally living in two worlds at once. Galadriel seems so odd and other worldly because she literally is living in two different worlds. Blanchette is invoking the Uncanny Valley to show that Galadriel is a woman who doesn't quite live at the same level of existence as those around her.
The Account of Isildur which Gandalf reads, where Isildur details his claiming of the One Ring, has some disturbingly familiar language in it. Although it's a bit more formally and flowery-worded, the Account is basically Gollum's ranting about the Ring; Isildur at one point says that it is Precious to him. He's only had the Ring for a short time and already it's starting to warp his mind.