** spoiler alert **
With the Fellowship of the Ring we had the introductions made, the journey started, and the fellowship already headed for disaster. The Two Towers picks up right where its predecessor left off and shows the same potential dark endings while offering some up.
In book three we see Aragorn, Gimli, and Legolas off hunting to retrieve Merry and Pippin from Saruman's orcs. The Three Hunters eventually see hope returned to them in the return of Gandalf (now Gandalf the White). While the four of them ride to Rohan's aide Merry and Pippin are introduced to Treebeard and the Ents, who rise up and overthrow the industrial waste that Orthanc has become. It is as astonishing as the later Battle of Helm's Deep to read. Two victories are amazing but you still can't help but feel that there is still so much more to accomplish and that this is just one little bit of progress. The same happens in the wake of the battle when Gandalf casts Saruman down and Pippin takes a gander into the palantir.
You gain so much and then still seem to loose it all. This continues in book four where we journey with Frodo and Sam into Mordor. They makes progress, they get lost, they meet Gollum and that works out fine for awhile until they try Gollum's infamous shortcut.
Here we see what the Ring will do to you first hand. Frodo is confronted with what he will become if he is not careful. It's something that plagues him and Sam throughout - I feel as though Sam is just watching this transformation and that is part of the reason that he hates Gollum so much.
They meet Faramir of Gondor and he succeeds in letting the Ring go where his brother, Boromir, had failed.
What really stands out for me are the final two chapters: the battle with Shelob and then Sam's dilemma. Frodo appears dead and Sam makes the choice to go on and carry on the quest without him. Then he turns right around and goes back to his Master, a choice that we may see as cowardly and weak but I see as a choice to stay with a friend (or else his heart showing him that Frodo wasn't dead after all). His loyalty is what makes it possible for Frodo to be saved.
We end with Sam senseless at the gates of Cirith Ungol, Frodo a captive, Gollum on the loose, Mordor massing, Rohan massing, Pippin and Gandalf riding to get Gondor going. Everything is getting ready and rearing to go but it just seems like a snowball's chance in hell for the good guys despite everything. Especially with the state the quest is in when you leave it.
It's hard going at points, lots of walking or talking, but it's worth it. Then we get onto the Return of the King, where the final stand will take place.