The La Fleur restaurant has a slew of unusual phenomena. Bonnet-clad apparitions pass through walls, blood leaks from ceilings and rats besiege the dining room. Experts from the Great Essex Witch Museum are called in to quell these strange sights. But before Rosie Strange and Sam Stone can do their thing events turn darker. For La Fleur's chef has been strung up and slaughtered like a pig. More oddly, the only witness, the owner's daughter Mary, swears blind a ghost did it.

Rosie and Sam must find out what's happening before Mary takes the fall. But intuitions and tip-offs lead them stumbling into the dark waters of the past, exposing secrets of a wider conspiracy, as well as secrets all Rosie's own. With strange chills Rosie and Sam learn that seeing isn't always believing, while thoughts of truth may be just as illusory.