The Secret of Moon Castle
by Enid Blyton
Prince Paul Baronsky's family is visiting England, and his family is willing to rent a castle to stay for a few weeks. Mrs. Arnold was asked to help find a suitable fort that knew England much better than Paul's parents. The Arnolds are invited to spend some time with them in the castle, and soon they are stunned by the strange events that occur in the castle: strange sounds, eyes on mysteriously glowing portraits, lights shining in the tower rooms despite the fact that they are tightly locked. It seems that there are unknown people who do not want them to stay in the castle. Sometimes, they feel a strange tingling effect, and strange colored lights seem to rise from the ground, and this seems to be due to a strange metal (possibly radioactive) that the mysterious men extracted for unknown reasons.
