Posy has always been able to see ghosts. She just didn't expect one of them to be a huge dog that guards a graveyard! When she and her family move to a small town with a bloody history, that's just what Posy finds - a Church Grim. In a creepy graveyard next to an abandoned church, The Grim appears to Posy and unlocks a sinister mystery. Together with her sulky step-brother, Wes, Posy must discover an unthinkable truth in order to find out what The Grim wants, and right the wrongs of the past.