Prince Caspian is in terrible danger when his wicked uncle, King Miraz, decides to get rid of the young heir to the throne. In desperation, Caspian blows the magic horn, calling on Peter, Susan, Lucy and Edmund in Narnia's hour of need.

Johnny didn't expect to end up with Kaspar, the Savoy cat, on his hands forever, and nor did he count on making friends with Lizziebeth, a spirited American heiress. Pretty soon, events are set in motion that will take Johnny - and Kaspar - all around the world, surviving theft, shipwreck and rooftop rescues along the way.