The kids from the Upper World must travel back in time to save Droon from the most dangerous creatures they¹ve met yet!
作者簡介：
Tony Abbott is the author of more than thirty funny novels for young readers. Since childhood he has been drawn to stories that challenge the imagination, and, like Eric, Julie, and Neal, he often dreamed of finding doors that open to other worlds. Now that he is older, he thinks he may have discovered some of those doors. He calls them books.