Armies clash for the first time in the trilogy at Helm's Deep. The battle marks a transition in Middle-earth: the Rohirrim, fighting from their previously impregnable fortress, use traditional weapons, including swords, bows, and, when possible, their horses, but Saruman has fielded a modern army. The explosives that take down the Deeping Wall appear to be the first use of gunpowder in Middle-earth, and along with Saruman's new super-breed of orc soldier, the hybrid Uruk-hai, constitute a new, industrial, and highly destructive mode of combat. The Rohirrim prevail, but the high cost dramatizes the cost of waging modern warfare.
Tolkien uses a flashback to describe the fall of Isengard, shifting the narrative away from the third person to the voices of the hobbits. The little people have moved away from the center of the narrative — Frodo and Sam have not made an appearance yet in this book — and the technique gives them some voice. This comes at the expense of pacing, because a flashback tends to slow the storyline down, even if it describes an exciting conflict.
For the first time since Gandalf described his imprisonment at the Council of Elrond, Saruman appears, garbed in his robe of splintered color. Saruman tries to tempt his audience; the power of his Voice is the power of seduction, telling each what he most wants to hear, convincing each to accept its twisted reasoning as his own. The most dangerous evils in Tolkien's world are not the orcs, who are visibly deformed and repulsive, but the evils that insinuate themselves through a false appearance of reason. Only when Gandalf strips Saruman of illusion do the onlookers see him truly: corrupt and twisted.
