Taran shouts to the king to call out the guard to help search for Eilonwy and Magg. The king, of course, thinks that the sea air has addled Taran’s brains, and asks why he accuses Magg of such an offense. Taran agonizes for about half a second over whether to reveal Gwydion’s secret, then tells all. He succeeds in convincing the king to call for Magg, who, naturally, cannot be found. The king then immediately believes Taran is telling the truth, which seems a little easy to me. King Rhuddlum forms two search parties, one headed by himself and one by Prince Rhun. Taking Taran aside, the king says he needs to speak to him about Rhun. Taran minces zero words in telling the king exactly what he thinks of the feckless prince. Then he tries to apologize, but it turns out the king is no dummy, and he’s quite aware of what a yutz his son is. He asks Taran to take an oath.
No, not that oath. Rhuddlum wants Taran to watch out for Rhun and make sure no harm comes to him. After all, he’s betrothed to Eilonwy. Taran is like, wait a sec, you mean my Eilonwy? Yes, that was the whole reason they brought her to Mona to begin with. Poor, tortured Taran gives his word to look out for his rival: “Your son will come to no harm if it lies in my power to keep him from it.”
As the search parties depart, Taran sends Kaw ahead as a scout. Fflewddur, riding alongside Taran, tries to reassure him that Eilonwy will be fine. Taran bitterly asks if he means the future Mrs. Rhun. Fflewddur immediately gets why Taran is so upset, saying he somehow always thought “despite all the squabbling and bickering between the two of you” that Eilonwy would end up with Taran. Taran reminds him that Eilonwy is a princess and has to marry one of her rank, and lies that he has never hoped for more. Fflewddur’s not buying it.
They ride on with no sign of Eilonwy or Magg. It’s nearly nightfall when Gurgi points out that Rhun has ridden off by himself and is likely to get lost. “Then cheerful hullos will turn to sad moanings and groanings!” The Master of Horse sounds a signal horn for the warriors to gather and make camp, but Rhun doesn’t return. Taran worries that Rhun may have fallen off his horse and gotten injured. He decides to head into the grove where Rhun was last seen. The companions lead their skittish horses through a wood filled with flickering, sinister shadows. Finally the horses refuse to go any farther, and an exhausted Taran agrees that it’s useless, Rhun is lost, and they should turn back. But Fflewddur points out that “unless you or Gurgi knows where we are, I rather suspect we’re lost, too.”