Charlie, Anna, and Emily must overcome their differences and work together to solve various puzzles leading to the secret treasure a famous female explorer left in Idlewood Manor before the adults do.

When timid Elizabeth's father takes her and her fearless friend, Zenobia, to his family home, Zenobia becomes obsessed with finding a ghost there, and then Elizabeth learns she had an aunt who disappeared from the house years ago.

"When Felix gets a crush on his friend Lily, who was adopted from China as a baby, he decides to try to take her back in time to learn more about China. After being caught by Maisie, the twins find themselves transported to a small village on the Yangtze River, leaving Lily behind in the present. In China, the twins meet Pearl Buck in the days just before the Boxer Rebellion. With bandits chasing them, they flee to safety in Shanghai. The twins return...