The Silver Chair their quest. When the young man is tied to his chair, his "ravings" seem instead to indicate desperation to escape an enchanted captivity. After several threats, the youth finally begs the three to release him in the name of Aslan. Recognizing this as the fourth Sign, they hesitantly do so. The young man immediately destroys the silver chair. Free from enchantment, he thanks them and declares that he is the vanished Prince Rilian, kept underground by the Lady of the Green Kirtle as part of her plot to conquer Narnia. The Green Lady returns and tries to bewitch them all
The Silver Chair earthmen, who take them aboard a boat across the subterranean Sunless Sea to the city ruled by the Lady of the Green Kirtle. She herself is away, but her protégé, a young man, greets the travellers pleasantly. He explains that he suffers from nightly psychotic episodes, and during these episodes he must, by the Lady's orders, be bound to a silver chair; for if he is released, he will turn into a deadly green serpent and kill everyone in sight. The three travellers determine to witness the youth in his torment, as they sense it could be the key to