The dreadful nightfall. Frodo and Samwise leave the road and turn south to Mount Doom. Third assault on Lórien.
"Mount Doom", by Alan Lee
"So the desperate journey went on, as the Ring went south and the banners of the kings rode north."
This is the "dreadful nightfall," four days since Frodo and Sam escaped the orcs and continued to travel the road to Orodruin. Tolkien calls it their hour of "blank despair"--Frodo has not spoken all day and walks stumbling and bent over, shrinking from the Eye that never ceases to watch him. He is nearly at the end of his will's endurance; Sam notices that he spends much of his time alternately reaching for the Ring and withdrawing his hand from it as he masters himself yet again. "Now as the blackness of the night returned Frodo sat, his head between his knees, his arms hanging wearily to the ground where his hands lay feebly twitching." Darkness covers the land, and Sam, somewhat stronger than his Master, turns to his own worries, particularly about Frodo's condition, and the fact they have no water left. He can do little about either, and finally rests. But his sleep is broken by sounds and lights and cries, both real and imagined --and by the pale lights of Gollum's eyes.
Tolkien's evocation of the hobbits' utter emotional exhaustion leaves the reader wounded as well; we grieve with the suppression of Frodo's essentially optimistic nature, and begin to realize that no matter how the quest turns out, he will never be same. Perhaps nothing else lost in the War of the Ring hurts as much.
In Lorien, Galadriel and Celeborn's Elves repel the third assault from Dol Guldur; the enemy will not be able to regroup before Sauron's defeat, and Dol Guldur will fall to Lorien.