Max fears that his family will disapprove of his friendship with Darla, a common girl from the village outside his uncle's fortress walls. That's why they meet secretly to read together from an old book, which she has found in a dusty room near the fortress laundry where she works. They read about a lost lake and feel adventurous when they slip out of the fortress to go swimming there; but the trouble begins when they find that, in the meantime, the fortress has been sealed and they can't get back in. It's lucky that they have the book with them, to guide them through the many dangers that...