This is a truly interesting book, because it takes place entirely within the world of Narnia and the surrounding lands – in fact the whole book technically takes place within a sentence from “The Lion, the Witch and the Wardrobe” – and the children from our world barely appear.
Shasta is a boy who overhears his father arranging to sell him to a passing lord – which is when he finds out his “father” found him, the only survivor of some seafaring disaster, and took him in (not out of compassion; Shasta is essentially a slave and his facial features show he is of Narnian birth). He considers running away, and is more than slightly surprised when the lord’s horse advises that he do so. The horse was taken from Narnia as a colt, and brought to a much more “civilised” world where he has been pretending to be a normal horse for most of his life.
And so the horse (Bree) steals the boy, and their escape to Narnia begins. They soon fall in with a second talking horse and a local girl who is fleeing an arranged marriage. The horses get along rather better than the humans do, since the local girl is rather high-class and Shasta is anything but.
There are lion attacks, breathless flights, haunted tombs, and our heroes accidentally discover a plot to take Narnia by force. It’s all very exciting J
The cloud was bigger and thicker than it had looked at first and soon the night grew very dark. Just as Shasta was saying to himself, “We must be nearly at the sandhills by now,” his heart leapt into his mouth because an appalling noise had suddenly risen up out of the darkness ahead; a long snarling roar, melancholy and utterly savage. Instantly Bree swerved round and began galloping inland again as fast as he could gallop.
“What is it?” gasped Shasta.
“Lions!” said Bree, without checking his pace or turning his head.
Rating: PG. I’d call it absolutely G and safe for anyone, but one character is a close parallel to Jesus Christ (in one of the later books this character clearly states that he exists on Earth as well, is known by a different name there, and that the children have been brought into Narnia so that they can more easily recognise him on Earth), and some atheists have found that offensive. The books do focus on the adventures, rather than allegory about 95% of the time.