Chronicles of Narnia, The: The Silver Chair
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Deep underground, a web of evil magic holds a prince in captivity.
Narnia … where owls speak, where evil weaves a spell … where sorcery enslaves the land.
Narnia is in peril, and only Eustace and Jill can help. Along with Puddleglum, a gloomy but valiant Marsh-wiggle, they are sent by the mighty lion Aslan to find Prince Rilian, heir to the throne. Their quest leads them past hungry people-eating Giants, and deep into the dark underground. But the true test for this noble band of friends comes when they face an evil witch and her deadly enchantments.