The Return of the King, the final novel in Tolkien’s The Lord of the Rings trilogy, picks up immediately where the previous installment, The Two Towers, left off. Frodo and Sam, two hobbits from the peaceful land of the Shire, are reaching the end of their quest to destroy the Ring—the weapon of the antagonist, Sauron—in the flames of Mount Doom. Minas Tirith, now the strongest city of Men, prepares for war against Sauron, whose is returning to his full strength. Aragorn, Legolas, and Gimli—three of the nine members of the Fellowship who set out to destroy the Ring—have just assisted the people of Rohan in their battle against Saruman’s army at Helm’s Deep and are planning their next moves. And Gandalf, a wizard and the orchestrator of the Fellowship, has miraculously returned from his fatal fall into the depths of Khazad-dûm and is proving increasingly necessary in the struggle of Middle-earth’s free people—namely, hobbits, Elves, Dwarves, and Men—against Sauron’s armies of orcs and Southron men.
After Pippin, one of the other two hobbits of the Fellowship, used the Seeing Stone he found at Isengard and accidentally revealed himself and a few details of the Fellowship’s journey to Sauron, Gandalf decided to take him to Minas Tirith. This is to ensure Sauron doesn’t think the Ring, which he knows is in the hands of a hobbit, is travelling with the Rohirrim. Gandalf wants Sauron’s full attention on Minas Tirith, not searching for the Ring—if Sauron is able to locate and reclaim the Ring, there’s no way the free armies will be able to defeat him.
After days of furious riding, Gandalf and Pippin arrive at Minas Tirith, the walled city of Gondor. During their journey, they saw beacons lit on the hills: war is approaching, and Gondor needs help. Gandalf takes Pippin to meet with Denethor, the Steward of Gondor. Despite Gandalf’s warning not to say much to Denethor, Pippin ends up offering him his service and is sworn in as a Guard of the Citadel. To his great frustration, Gandalf quickly realizes that Denethor is unwilling to take advice on the subject of Gondor’s battle strategy. While Gandalf attends council meetings, Pippin roams the city. He sees a huge shadow growing from Mordor and begins to understand that war is on Gondor’s doorstep.
Meanwhile, Merry, Aragorn, Legolas, and Gimli ride to Helm’s Deep with Théoden and his guard. As they ride, they are approached by a group of Dúnedain Rangers—friends of Aragorn. The Rangers brought advice from Elrond to consider taking the Paths of the Dead, and when Aragorn decides, after using the Seeing Stone to communicate with Sauron, that he will approach Minas Tirith via that route, Théoden resigns himself never to see Aragorn again.
When the Rangers arrive at Dunharrow, Éowyn greets them. She attempts to convince Aragorn to allow her to ride with them and is distressed when he refuses. Aragorn and his men make their way along the Paths beneath the Haunted Mountain, where the silence and darkness spook the men and their horses. They emerge from the mountain caves and sense the army of the Dead following them—Aragorn has fulfilled the prophecy as heir to the throne of Gondor and called on them to fulfill their longstanding oath.
Merry becomes Théoden’s esquire and rides to Dunharrow with him, where the Rohirrim have gathered. But Théoden releases Merry from his service in anticipation of battle, and Merry is adamant that he won’t be left behind while everyone he loves has gone to war. A Rider called Dernhelm takes him on his horse secretly, hidden beneath his cloak. Rohan’s riders muster to assist Gondor in battle, despite the enemy encroaching on their own lands.
The shadow has covered the lands of Gondor and Rohan. Faramir’s company returns to Minas Tirith from Ithilien, and on their approach to the city, they’re assailed by Black Riders. Faramir’s return brings the people of the city joy, but his father, Denethor, greets him coldly and suggests that Gondor’s fate would be more hopeful if Faramir had died in his brother Boromir’s place. Faramir brings the news that Frodo and Sam are taking the Stairs of Cirith Ungol to reach Mordor. Though Gandalf worries about their safety on this path, he is reassured to know that Frodo and Sam have been seen alive so recently.
Denethor commands Faramir to lead the defense of Osgiliath. It’s a hopeless battle, but Denethor refuses to let the city go without a fight. Mordor’s armies, led by the Lord of the Nazgûl, quickly swarm Osgiliath and destroy Minas Tirith’s outer wall. Faramir is gravely wounded, and his men have been scattered and decimated. When Denethor sees Faramir’s deathlike body, he resigns himself to despair. He sits beside his son and refuses to command his besieged city’s troops.
While Minas Tirith burns and its soldiers succumb to despair, Denethor takes Faramir to the House of the Steward where he plans to burn himself and his son alive. He orders Pippin to fetch wood and oil. Pippin goes to find Gandalf instead, who is being challenged by the Lord of the Nazgûl. A horn rings out: the Rohirrim have arrived, and the Lord of the Nazgûl flies off to join the battle, leaving Gandalf to save Faramir. Gandalf tries to convince Denethor to hold onto hope that Gondor will survive. But Denethor, having looked into the Seeing Stone, believes that hope is foolish. When Gandalf takes Faramir away, Denethor lights the funeral pyre, throws himself onto it, and burns to death.
Upon the arrival of the Lord of the Nazgûl on the battlefield, Théoden is crushed by his spooked horse. Dernhelm comes to Théoden’s defense. When Dernhelm removes his helmet, Merry realizes that it’s actually Éowyn he’s been riding with. He assists her in her defeat of the Nazgûl who, though he claims he cannot be defeated by a man, is left vulnerable to the attacks of Merry, a hobbit, and Éowyn, a woman. When the Lord of the Nazgûl is defeated, the oppressive shadow disperses.
Though the Rohirrim had early success defeating Mordor’s front lines, they are outnumbered by the enemy armies who continue to approach Minas Tirith. Their victory is only won when Aragorn and his company arrive on the Black Ships, unfurling the royal banner of Gondor.
The wounded, including Faramir, Éowyn, and Merry, are taken to the city’s Houses of Healing. The Healers have little success saving the sick from the affliction of the Dark Shadow, which is caused by proximity to the Nazgûl. It’s only Aragorn’s skill that revives the patients. Though he’s the heir to the throne, Aragorn refuses to claim kingship yet, camping outside the city while Imrahil takes on temporary stewardship. Aragorn and the other captains meet to strategize what they predict will be their last act of war—they’ll march on the Black Gate of Mordor in the hope of drawing Sauron’s attention away from Frodo, whose quest to destroy the Ring must be successful if there’s to be any peace in Middle-earth again.
While battle rages at Minas Tirith, Sam rescues Frodo from the orcs at the Tower of Cirith Ungol and accompanies him through the treacherous fields of Mordor to reach Mount Doom. They don’t have enough food or water for the return journey, and the burden of the Ring is becoming unbearable for Frodo. They finally reach the chasm of Mount Doom, but Frodo refuses to give up the Ring. Gollum, having followed the pair through Mordor, attacks Frodo and bites the Ring off his finger, dancing in joy before falling into the mountain’s fiery core and destroying the Ring as he dies.
At the moment of the Ring’s destruction, Aragorn’s armies are fighting a hopeless battle at the Black Gate. They’re vastly outnumbered and on the verge of defeat when the enemy suddenly cowers and retreats: Sauron has been defeated. As Mordor crumbles, the great Eagles arrive as a favor to Gandalf, who takes them to rescue Frodo and Sam from the molten ruin of Mount Doom.
Sam and Frodo are honored on their return to Gondor, and they talk and rest with Merry, Pippin, Legolas, and Gimli. Eventually, Aragorn returns to Minas Tirith to claim his kingship at last. He begins his reign with several merciful acts and replaces the withered White Tree in the Citadel courtyard with a sapling that has descended from it, marking the beginning of a new, flourishing age of Men.
Frodo, Sam, Merry, and Pippin travel home to the Shire, escorted by Gandalf. Frodo insists that they stop in Rivendell on their journey to see Bilbo, whose old age has caught up with him now that the Ring has been destroyed. When the hobbits finally return to the Shire, they find it has been overtaken by ruffians led by Frodo’s relative, Lotho. They corral an army of hobbits to rebel against the ruffians, and in their victory, they realize that Lotho has been used as Saruman’s puppet. Frodo banishes Saruman from the Shire, refusing to use violence against him—but Saruman’s servant, Wormtongue, slits Saruman’s throat before being shot down himself.
A few months after returning home, Frodo realizes that he will never fully heal from his wounds or the burden of the Ring. The next year, when Elrond, Galadriel, and Gandalf—the bearers of the Three Rings—make their way to the Grey Havens with Bilbo, Frodo joins them. After bidding farewell to the other hobbits, they sail from Middle-earth to the Undying Lands together.