Middle Earth is on the verge of falling, and Sauron's vast armies are about to swarm mankind's last defenses. Only two things can save us: a lost king returns to his throne, and a little hobbit makes it to Mount Doom. 
 Yes, there's a lot of tension in "The Return of the King," the brilliant, rich conclusion to J.R.R. Tolkien's epic fantasy saga. And rather than cheaping out with a "and they all lived happily ever after," Tolkien gives his saga's finale a bittersweet edge, along with plenty of wild battles and good vs. evi.. 
 Gandalf has ridden to the city of Gondor with Pippin (partly to keep him out of trouble), where the forces of Mordor are attacking. There is upheaval in the city itself, as the steward of Gondor is going nuts. Merry pledges his service to King Theoden of Rohan, not knowing what is ahead for the king and his relatives. And Aragorn is seeking out allies to fight Sauron on a military scale, even if they can't defeat him unless the Ring is destroyed. His search will take him to tribes of forest-dwellers, to Gondor -- and even to summon an army of the dead. 
 In Mordor, the unconscious Frodo has been captured by Sauron's orcs, and taken to the fortress of Cirith Ungol. Sam is desperate to free his friend, but knows that he can't take on an army, and that Frodo would want him to finish the quest. Sam manages to free Frodo from captivity, but they must still brave more dangers before they can come to Mount Doom, the only place where the Ring can be destroyed. As they travel Sam sees Frodo slipping further and further into the Ring's grasp. Will Frodo be able to destroy the Ring? 
 Usually, the climax of an epic adventure is a disappointment. "Return of the King" succeeds in almost every way, wrapping up each individual storyline, one by one. The ending has a feeling of finality; this is one story that could never have a sequel; Tolkien shows that in a war like this, there is no true "happy ending." Even if the good guys win, there will still be scarring, and death, and haunting memories of what once happened. And even if a person survives, he will never be the same. 
 This is the grimmest of the three books in this trilogy. Frodo and Sam are stuck in the vividly horrific Mordor, while the city of Minas Tirith is on the verge of completely crumbling. Tolkien does a phenomenal job of exploring the madness, despair, rage and sorrow that accompany a war, and the way it can affect even the idyllic Shire. And he doesn't forget the slow period of healing that follows -- for people, for civilizations, and even for nature. 
 Though a section of the book near the end descends into near-biblical prose, which changes post-Gondor, Tolkien does not waver in his ability to evoke emotion. One of the most touching scenes in the book is when Sam finds Frodo naked, unconscious and being beaten by an orc. Others include Merry's farewell to Theoden, Eowyn's slaying of the Witch-King, and of course the bittersweet final scene. 
 Speaking of Frodo, this trilogy's hero is almost unrecognizable in parts of this book. The bright, naive young hobbit of the first book has been worn down to a pale shadow of himself. As he grows increasingly attached to the Ring, we even see him doing what seems unimaginable: threatening Sam with a dagger. Sam has come a long way from the shy young hobbit who couldn't say a word around the High Elves -- now he's attacking orcs and carrying Frodo to Mount Doom. 
 And the supporting characters are not neglected either, with the younger hobbits being exposed to the horrors of war, Aragorn breaking fully into his role as the future king of Gondor, and passionate war-maiden Eowyn affecting the war as nobody else could. Some much-loved characters are lost, and others will be permanently changed. 
 The story doesn't really end on the last page; for more background, especially on Aragorn and Arwen, readers should also read the appendices at the end of the book. Another good addition is "The End of the Third Age," in which the unpublished epilogue of this book can be found. Though this is probably not canonical, it nicely concludes the story and is a heartwarming look at what happens in the years following "Return of the King." 
 It's difficult, once the story has finished, to accept that one has to say goodbye to Middle-Earth and its enchanting inhabitants. But as Gandalf says, "I will not say: do not weep; for not all tears are an evil."