When twins Dropfire and Phantom yield over to their curiosity, trouble always follows. It is clearly understood that the room of conditions in the castle of Um is forbidden and only those who have studied, trained, and gained ample knowledge under very strict guidance can enter the wing. But amidst Father Iyle's and Lady Saphodil's customary reminder, the twins' inquisitiveness always triumphs. Read on and join the twins and their faithful pets, Birthday, the crow, and Excessive, the continuously talking cat, in their epic journey in The Adventure at the Castle Endures.