Greta and the ghost hunters

Greta Woebegone did not believe in ghosts, until the day she almost died, when everything changed. Now Greta can not only see the spirits that haunt her family home, she can talk to them too, from Percy the poo-pushing plague victim to the sinister spook in the cellar. Can Greta save the ghosts from being exorcised (a fate worse than undeath)? Can the ghosts help Greta stop her beloved Grandma being put in a home? And can any of them find the courage to face up to the traumas in their pasts that are holding them back from the future?