Felicia Cartright and the Lone Ski Boot — Bernard Palmer

Emma, the new Cuban girl at Wellington School for Girls, has been uncharacteristically sad and quiet. Felicia and Joan learn the reason is that Emma's uncle and the money he promised for her education are missing. So when Emma is given a mysterious letter and a key, the girls try to find what the key unlocks but, in the process, find themselves chased by spies and caught up in international intrigue.