¥Eustace (from #3, Dawn Treader) and Jill are called into
Narnia by Aslan to find and rescue Prince Rilian from a wicked witch, the Queen of
Underland.
¥Accompanied by a marsh wiggle Puddle-glum and guided by
four clues, the two travel into the wild north in winter.
¥In spite of botching nearly all the clues, they do succeed
and the story ends more or less happily.