Frodo Baggins
The Ring-bearer. Frodo carries the One Ring into Mordor, but the Ring breaks him down over the journey. He fails at the final moment, claiming the Ring rather than destroying it. His wound never fully heals, and he eventually leaves Middle-earth. His arc shows that some burdens change a person beyond recovery.
Samwise Gamgee
Frodo's companion and the book's quiet center. Sam carries Frodo up Mount Doom when Frodo can no longer walk. He briefly holds the Ring himself and gives it back. He organizes the Scouring of the Shire and returns to his family at the end. Tolkien treats Sam as the true hero of the quest.
Aragorn
The rightful heir to Gondor's throne. Aragorn leads the Paths of the Dead, commands the Battle of Pelennor Fields, and marches to the Black Gate as a distraction for Frodo. He is crowned King Elessar and marries Arwen. His arc is about accepting a destiny he has spent decades avoiding.
Gandalf
The wizard who coordinates the defense of the West. Gandalf holds Minas Tirith together while Denethor collapses, leads the council that decides to march on the Black Gate, and guides the strategy of the war. After the Ring is destroyed, he sails west with the Elves. His power in Middle-earth is finished once his purpose is complete.
Éowyn
Niece of King Théoden and shieldmaiden of Rohan. Forbidden from fighting, she disguises herself as a soldier and rides to battle. She kills the Witch-king, the act that turns the battle at Pelennor Fields. Afterward she falls in love with Faramir and chooses a life away from war. Her arc challenges who gets to be a hero.
Gollum
The creature who carried the Ring for centuries. Gollum follows Frodo into Mordor, driven entirely by his obsession with the Ring. He attacks Frodo at Mount Doom and bites off his finger to get the Ring back. His fall into the fire destroys the Ring. He is the accidental agent of the quest's success.
Denethor
Steward of Gondor and Faramir's father. Denethor is capable and proud, but he has been using a palantír that Sauron corrupted. He falls into despair, tries to burn himself and Faramir alive, and dies in the flames. His arc shows what happens when a great mind gives up.
Merry
One of the four hobbits. Merry rides to battle with the Rohirrim and strikes the Witch-king from behind, allowing Éowyn to finish him. He is wounded by the Witch-king's dark power and recovers. He helps lead the Scouring of the Shire. His arc tracks a hobbit who becomes a soldier.
Pippin
The youngest hobbit. Pippin pledges service to Denethor in Minas Tirith and helps save Faramir from the pyre. He fights in the battle at the Black Gate. He helps lead the Scouring of the Shire. His arc is about a reckless young hobbit growing into someone reliable under pressure.
Faramir
Denethor's younger son and captain of Gondor. Faramir is nearly killed in battle and nearly burned alive by his own father. He recovers in the Houses of Healing and falls in love with Éowyn. He becomes the Steward of Gondor under Aragorn's rule. Unlike his father, he accepts the return of the king without resentment.