The Uruk-hai
‘I serve no man,’ said Aragorn; ‘but the servants of Sauron I pursue into whatever land they may go. There are few among mortal Men who know more of Orcs; and I do not hunt them in this fashion out of choice. The Orcs whom we pursued took captive two of my friends. In such need a man that has no horse will go on foot, and he will not ask for leave to follow the trail. Nor will he count the heads of the enemy save with a sword. I am not weaponless.’
The Two Towers, Being the Second Part of the Lord of the Rings, Book 3, ch. 2, pg. 423.
While the Three Hunters raced across the East Emnet through Rohan, Frodo and Sam departed to the East. Through the Emyn Muil they wandered until encountering Gollum, at last. After taming the creature, Frodo bid him to lead them to the Black Gate. Thus, Smeagol led the Hobbits through the Dead Marshes and to the very teeth of Mordor.
Helm’s Deep
‘Come!’ said Aragorn. ‘This is the hour when we draw swords together!’ Running like fire, they sped along the wall, and up the steps, and passed into the outer court upon the Rock. As they ran they gathered a handful of stout swordsmen. There was a small postern-door that opened in an angle of the burg-wall on the west, where the cliff stretched out to meet it. On that side a narrow path ran round towards the great gate, between the wall and the sheer brink of the Rock. Together Eomer and Aragorn sprang through the door, their men close behind. The two swords flashed from the sheath as one.
The Two Towers, Being the Second Part of the Lord of the Rings, Book 3, ch. 7, pg. 521.
The Road to Isengard
‘Once he was as great as his fame made him. His knowledge was deep, his thought was subtle, and his hands marvellously skilled; and he had a power over the minds of others. The wise he could persuade, and the smaller folk he could daunt. That power he certainly still keeps. There are not many in Middle-earth that I should say were safe, if they were left alone to talk with him, even now when he has suffered a defeat. Gandalf, Elrond, and Galadriel, perhaps, now that his wickedness has been laid bare, but very few others.’
The Two Towers, Being the Second Part of the Lord of the Rings, Book 3, ch. 9, pg. 553.
As Frodo and Sam came upon the Black Gate, the passage was closed to them. Gollum convinced the pair to journey to Mordor by way of the Cross-roads in Ithilien. Gollum’s guidance proved treacherous, as he led them into the lair of Shelob the Great. Aragorn, Legolas, Gimli, and the rest of the Fellowship could now only wonder, and hope, that Frodo and Sam could succeed in their task….
The Return of the King
The Book of Elessar 