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The Lion, the Witch, and the Wardrobe is a fantasy novel for children by C. S. Lewis. It was the first of the Chronicles of Narnia to be written, in 19??, and is the best known. The Magician's Nephew is thus a "prequel".
The book concerns the adventures of four English children, Peter, Susan, Edmund, and Lucy. They are staying in a large, old house owned by on old professor to escape the dangers of WWII. Whilst playing a game of hide and seek, Lucy enters a wardrobe, and finds herself in a snow-covered forest (which curiously features a lighted lamp post). She meets Mr Tumnus, a faun, who befriends her. Over tea and buttered toast, Mr Tumnus intimates that Narnia is in thrall to a tyrant, the White Witch, who turns her enemies into stone, and has made it "always Winter, but never Christmas".
When Lucy returns, she is surprised to discover that the other children have not noticed her long absence. She takes them into the wardrobe, but it is just a normal wardrobe, with a solid wooden back.
Some time later, both Lucy and Edmund enter Narnia. Lucy meets Mr Tumnus again, but Edmund encounters the White Witch herself, and her Dwarf. She gives him Turkish delight, and extracts details of what he knows.
On their return, to Lucy's disgust, Edmund pretends that he has not really been in Narnia. Peter and Susan speak to Professor Wotsit about their concern that Lucy persists in treating her "made up story" as real, but the professor refuses to dismiss it. Rather, he defends Lucy, asking the others to compare her record of truthfulness against Edmund's.
Finally, all four children go into Narnia. They discover that Mr Tumnus is missing, and his house has been ransacked. They meet Mr and Mrs Beaver, who speak of Aslan who is rumoured to be arriving to save Narnia. They prepare to set off on a journey to Cair Paravel to meet Aslan. They notice that Edmund has disappeared, and realise that he had, in fact, been in Narnia before, and has betrayed them. Along the way, they are overtaken by Father Christmas, who gives them all useful presents, and hints that the power of the Witch is waning.
Meanwhile, Edmund has met up with the White Witch, and with her and her dwarf is also travelling via sledge. Along the way, they come across an entire party of animals which is celebrating Christmas with a feast provided by Aslan. The enraged Witch turns them all to stone. Eventually, they have to abandon the sledge, as snow is gradually thawing.
The other three children meet Aslan. There is a parley with the Witch, which results in the ashamed Edmund being released. It later transpires that the price for this is that Aslan has agreed to forfeit his own life. He is slaughtered by the Witch and her horrible forces on the Stone Table.
But as dawn breaks, a "Deeper Magic from before the Dawn of Time" raises Aslan from the dead, and the Stone Table is broken in two.
The Witch is vanquished, and the four children become the Kings and Queens of Narnia.
After many years' reign, they find once again the lamp post in the forest, and return to England, where no time has passed since they left.