Chosen Ones and Flight of the Outcasts, by Alister McGrath

Alister McGrath, one of modern Christianity's foremost theological voices, is writing children's books. The Aedyn Chronicles are a series in which two British siblings, Peter and Julia, are magically transported to the land of Aedyn, once a paradise, where it is their destiny to set things right.

For obvious reasons, no one gets very far into a discussion of the Aedyn series without mentioning the Chronicles of Narnia, by C. S. Lewis. In both series, a set of siblings living away from their parents journey to another world. In both series, the oldest of those siblings is named Peter. Both Aedyn and Narnia are in the throes of an ideological civil war, and the children's arrival is the fulfillment of a prophecy. And (Lewis and McGrath being eminent theologians) both series are examples of Christian allegory.

Children's allegorical fantasy has long been a favored medium for theologians. George MacDonald, C. S. Lewis, J. R. R. Tolkien and Madeleine L'Engle wrote the founding classics of the genre and remained its best-selling authors for decades. Then in 1995 Philip Pullman published Northern Lights (called The Golden Compass in North America), the first book of His Dark Materials, a trilogy that can be viewed as Narnia for atheists. His young heroes, Lyra and Will (British schoolchildren, yes; siblings, no), enter into another world's ideological struggle, fulfilling a prophecy, and in the end defeat God, thereby ridding the world of theism.