That's what Jack and Annie hear when the Magic Tree House takes them back to the time of the American Civil War. There they meet a famous nurse named Clara Barton and do their best to help wounded soldiers. It is their hardest journey in time yet - and one that will make the most difference to their own lives.
The 'Magic Tree House' series follows the adventures of 8-year-old Jack and 7-year-old Annie, a brother and sister who find a mysterious tree house filled with books in the woods near their home. The tree house belongs to Morgan le Fay, a magical librarian from the time of King Arthur, who sends Jack and Annie travelling through time and space to help free her from a spell. Each book is its own adventure, and with each book Jack and Annie move closer to becoming Master Librarians themselves!