The Ironwood Tree - The Spiderwick Chronicles

First a pack of vile, smelly goblins snatch Simon. Then a band of elves try to entrap Jared. Why is the entire faerie world so eager to get their hands on Arthur Spiderwick's Guide? And will the Grace kids be left alone now that the Guide has mysteriously disappeared? Don't count on it. At school, someone is running around pretending to be Jared. To make matters even worse, now Mallory has disappeared and something in the water is killing off the plants and animals. Clues point to the abandoned quarry just outside of town where the dwarves have taken over. Meanwhile, the faerie world's abuzz with the news that a creature with plans to rule the world has offered the dwarves a gift to join with him: a queen.