The Spiderwick Chronicles: The Field Guide - Book 1 by Tony DiTerlizzi and Holy Black

Celebrate the 20th anniversary of the international bestselling Spiderwick Chronicles with the first instalment in the adventures of the Grace children. 

After finding a mysterious handmade field guide in the attic of the ramshackle old mansion they've just moved into, the Grace children – Jared, Simon and Mallory – discover that there's a magical and maybe dangerous world existing parallel to our own – the world of faerie.   

The children want to share what they know, but the faeires will do everything possible to stop their secrets being revealed . . .