The Spiderwick Chronicles is a video game adaptation of the film of the same name.
The plot line mimics the movie's: When Jared, Simon, and Mallory Grace move into the Spiderwick estate, they discover the late owner's field guide to fairies. They soon discover a hidden world all around them, populated with creatures such as brownies, goblins, and sprites. However, Jared and his family are in grave danger, because Mulgarath, an ogre, wants to steal the book for himself.
The principle playable characters are Jared, Simon, and Mallory, and Thimbletack can be used to explore small areas. Each character has a unique weapon with which to fight against evil creatures. The Grace children can capture Sprites to give them special power-ups. In the Wii version, either the classic controller or the Wii Remote and Nunchuk can be used.
Source: Wikipedia, "The Spiderwick Chronicles (video game)", available under the CC-BY-SA License.