The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!

Jack and Annie are on a mission to find (and inspire!) creative people. This time, Jack and Annie meet an Irish girl and go on a magical adventure that changes the girl’s life—she grows up to be Lady Gregory, who helped bring back the Irish legends, started a theater, and helped the Irish people revive both their heritage and their pride.

Formerly numbered as Magic Tree House #43, the title of this book is now Magic Tree House Merlin Mission #15: Leprechaun in Late Winter.