As Theseus prepares to leave Eleusis, the Queen acts strangely. Theseus wonders if she is pregnant. Theseus meets up with the Megarians and attacks the stronghold of Sinis, a well-known robber who hideously tortures his victims. Theseus and the Companions easily defeat Sinis and his men, and, although Xanthos and Pylas divide the spoils evenly, Xanthos gives the Companions and Theseus a much smaller share. Theseus, speaking loudly enough for all to hear, praises his troops and splits his share among them, angering Xanthos and making his men happy. The armies wipe out several more strongholds, and Theseus is almost killed by three huge stones that fall down the hillside. The next day, they find the robbers whom they have not killed joined together for a final battle. It is Theseus' first battlefield experience, and his excitement and energy are tremendous. He has his charioteer drive him straight into the enemy forces to carve a path for the troops to follow, and he aims for a large man who seems to be in charge. Suddenly, he flies out of the chariot, losing his spear and his helmet in the process. Theseus lands on top of an enemy, and manages to kill the man with his knife. Soon the Companions come charging up, aiding Theseus, and the battle continues. It is over in a few hours.
Everyone rejoices after the victory. Pallas, one of the Companions, brings forward Theseus' charioteer, who was unhurt when the chariot's wheel came off. Pallas says that the man knew which way to fall before it happened, and Theseus begins to suspect foul play. He goes back to the chariot, examines it, and finds that the linchpin was made of wax. They question the charioteer and find that Xanthos forced the charioteer to commit treachery. Theseus executes the charioteer. Theseus talks with Pylas, who was wounded in the shoulder, an injury that he later dies from. They return to camp, and in front of all of the soldiers Theseus confronts Xanthos with his evidence of foul play. When the warriors become angry at their leader's treachery, Xanthos loses his temper. Theseus remains calm and suggests that they settle their dispute in combat. They begin to fight, with spear and shield, and Theseus decides to throw his spear. Xanthos is prepared, and blocks with his shield, which the spear penetrates. Now Theseus has only his sword against Xanthos' spear. As he is forced backwards, he hears a thud on the ground next to him and realizes that spears were thrown into the ground nearby for him to use. He grabs one, and, as Xanthos prepares to hurl his own spear, Theseus throws. His spear goes deep into Xanthos' ribs, and he soon dies. They feast, and then Theseus sleeps with the girl he chose as part of his spoils.
Theseus is a brave and strong warrior, but his ability to lead is what saves his life. He inspires great loyalty in his troops, and it is that loyalty that aids him in times of need. Theseus is almost killed due to Xanthos' treachery, but the loyal Companions come to his aid when he fell in the battle and he escaped relatively unscathed. Later, when facing Xanthos in combat, his men save him by tossing him spears to use. Although he is a foreigner, Theseus is good to his soldiers and treats them as equals, while Xanthos slights the Companions by giving them less than equal share of the spoils. Theseus knows the value of loyal men. However, Xanthos' treachery puts him in the wrong in several ways. Not only does he attempt to kill a person who is fighting on his own side, but that person is the king, who is not supposed to die before it is his time. Clearly, Theseus is not the only one who can change the customs of the land. Things are changing in Eleusis, and, although he precipitates the changes, Theseus cannot know what other changes will occur or what forms they will take. Although the wax linchpin and Xanthos' treachery clearly take Theseus by surprise, he sees that he must show that he still has mastery both over himself and the situation.
When the charioteer begs for his life, Theseus realizes that kings are often required to make difficult decisions. The king has to carry out justice, even if it is distasteful. Theseus learns that a king must act according to the requirements of the law, even if he would rather not. A king must think of himself as the leader of his people, more than as a man with his own desires and thoughts. The charioteer goes along with Xanthos because he is in fear of his own life, but Theseus must punish him nonetheless. Theseus has to expect more from people than they are willing to give, in order to maintain justice. Although he is merely a pawn, the charioteer is still guilty, and that guilt cannot remain unpunished.