When twelve-year-old twins Philippa and John discover that they are descended from a long line of djinn, their mother sends them away to their Uncle Nimrod, who takes them to Cairo where he starts to teach them about their extraordinary powers.
This was a rather neat idea, but I really didn't like the characters or the dialog much. It all seemed a bit cliche. Sometimes in children's novels the main characters (when children) have almost no personality at all, and it seemed John and Philippa did not really have moods or characteristics unique to them. And the evil characters did not seem driven by a motive or anything. They simply just chose the Bad side. It made them seem not as evil in a way.
I can see how many young readers would like this, but it really didn't hold my attention.