Super Short Summary

The Field Guide by Tony DiTerlizzi and Holly Black follows the three Grace children—Mallory, Jared, and Simon—who, after moving with their mother to a dilapidated Victorian mansion, encounter a mischievous boggart living within the walls. The children uncover a hidden library and discover Arthur Spiderwick's field guide to faeries, leading to a series of magical and troublesome events as they try to appease the creature and learn more about the secret world around them.