Déagol stumbles upon the One Ring while fishing in a river with his cousin, Sméagol. Enchanted by its power, Sméagol's desire leads him to commit a horrifying act, murdering Déagol and ultimately transforming into the creature known as Gollum. This act marks the beginning of a tragic descent into madness and physical corruption, forcing Gollum to seek refuge in the shadowy depths of the Misty Mountains.
Fast forward centuries to the War of the Ring, where the wise Gandalf orchestrates a gathering of allies, including Aragorn, Legolas, Gimli, and King Théoden of Rohan. Their mission leads them to Isengard, where they reunite with the courageous hobbits Merry and Pippin. In a tense moment, Gandalf seizes Saruman's palantír, a seeing stone, and heeds its warning of looming danger. The group returns to Edoras, celebrating their triumph at Helm's Deep. However, when Pippin gazes into the stone, he glimpses the dark power of Sauron and a blazing tree, prompting Gandalf to decipher the impending threat toward Gondor's capital, Minas Tirith. He rushes to deliver this crucial warning to the corrupt steward Denethor, while Pippin pledges his loyalty to the steward, recalling how Denethor’s late son, Boromir, saved him. On Gandalf’s guidance, Pippin ignites the beacons that signal for assistance from Rohan.
Meanwhile, the brave Frodo, the Ring-bearer, along with his loyal companion Sam, embarks on a perilous journey toward Mordor, unknowingly trailed by Gollum, who harbors treacherous intentions of reclaiming the Ring for himself. Their path crosses ominously with the Witch-king of Angmar, the malevolent lord of the Nazgûl, who leads an army of Orcs toward Gondor. In a deceitful maneuver, Gollum frames Sam for feasting on their provisions, deceiving Frodo into banishing his friend.
As King Théoden rouses his forces, the serene Elrond reveals heart-wrenching news to Aragorn; Arwen, his beloved, is in peril, a choice made to remain in Middle-earth. In a powerful gesture, Elrond presents Aragorn with Andúril, the legendary sword reforged from the remains of Narsil. He encourages Aragorn to claim his birthright as heir to the throne of Gondor. With Legolas and Gimli by his side, Aragorn braves the Paths of the Dead, promising to free the restless souls there from their eternal curse if they answer Gondor's call.
Gollum cunningly lures Frodo into the lair of the fearsome spider Shelob. A struggle ensues, resulting in Frodo's brief escape but subsequent paralysis at the hands of Shelob. Sam, returning just in time, fends off the creature and, believing Frodo dead, takes up the Ring, only to realize his grave error when Orcs capture Frodo. The bond between them strengthens as Sam bravely rescues Frodo, continuing their treacherous trek toward Mount Doom.
Despite receiving desperate orders from Denethor to lead a hopeless charge, Faramir returns gravely injured. The steward, driven mad by despair, attempts to destroy both himself and Faramir on a funeral pyre. With quick-thinking, Pippin alerts Gandalf, who intervenes just in time. Denethor, engulfed in flames, leaps to his demise.
The tides of war turn as Théoden leads his staunch warriors against the Orc hordes. A fierce battle erupts, leading to initial successes, but tragedy strikes as the Witch-king mortally wounds Théoden. In an act of valor, Théoden's niece Éowyn, with the help of Merry, vanquishes the Witch-king. However, Théoden succumbs in his niece's embrace. Aragorn, now armed with the strength of the Army of the Dead, fulfills their oath, and together they conquer Sauron’s forces.
Determined to create a diversion, Aragorn marches toward Mordor, drawing Sauron's forces away from Frodo and Sam. With their adversary distracted, the hobbits finally reach Mount Doom. Yet, Gollum, who survived a tragic fall, attacks them. In an intense struggle, Frodo succumbs to the Ring’s seductive power and dons it. In a desperate bid, Gollum bites Frodo's finger, reclaiming the Ring, but the two tumble down, leading to a cataclysmic end as Gollum falls into the molten depths along with the Ring, ensuring Sauron’s definitive defeat and the obliteration of his army.
As the dust settles and the land of Mordor collapses, Frodo and Sam narrowly evade destruction, thanks to Gandalf and the eagles. The remaining members of the Fellowship reunite in the restored city of Minas Tirith, where Aragorn ascends as the King of Gondor and weds Arwen, uniting their fates. The humble hobbits return to the peaceful Shire, and in a celebratory spirit, Sam marries Rosie Cotton. Yet, four years later, haunted by the memories of war and the ever-present pain from his past, Frodo departs Middle-earth for the serene Undying Lands alongside his uncle Bilbo, Gandalf, and the Elves, leaving Sam with the treasured Red Book of Westmarch, chronicling their extraordinary adventures.
