The Land of Stories. A Grimm Warning. Book 3: Chris Colfer

Conner Bailey thinks his fairy-tale adventures are behind him - until he discovers a mysterious clue left by the famous Brothers Grimm. With help from his classmate Bree and the outlandish Mother Goose, Conner sets off on a mission across Europe to crack a two-hundred-year-old code.
Meanwhile, Alex Bailey is training to become the next Fairy Godmother... but her attempts at granting wishes never go as planned. Will she ever be truly ready to lead the Fairy Council?
When all signs point to disaster for the Land of Stories, Conner and Alex must join forces with their friends and enemies to save the day. But nothing can prepare them for the coming battle... or for the secret that will change the twins' lives forever.
The third book in the bestselling Land of Stories series puts the twins to the test as they must bring two worlds together!