"Tuesdays at the Castle" is the first book in the popular children's series by Jessica Day George, set in a fascinating world where a castle reshapes itself. Every Tuesday, the castle surprises its inhabitants with new rooms, towers, or even entire wings. The protagonist, Princess Celie, is the only one who maps the changes and knows the secrets of the castle. When the king and queen are in danger, it falls to Celie to protect her home and her kingdom. This captivating story weaves together adventure, magic, and the power of courage and determination.