I think I may have read this as a child as it was familiar but I picked it up this time to read it when my daughter read it for AR points at school. It is a cute story with just enough mystery and spookiness to keep a child reading along. Harold the dog and Chester the cat are at home when their family arrives back at the house with a small rabbit they'd found at the Dracula movie they went to see. Christening him Bunnicula, the family decides to keep our bunny and that is when things around the house start getting a bit strange. Chester the cat becomes convinced that the new bunny is in fact a vampire rabbit and goes to great lengths to try and convince the more skeptical Harold. But when vegetables in the family's refrigerator start turning up limp and white and drained of their juices speculation turns to a certainty of sorts.
What Chester and Harold do about this strange new member of the family and how they each react to the mysterious little bunny forms the bulk of this short children's chapter book. While the book is a children's book, it does a good job of being engaging enough to not have any adult readers (or perhaps it would be better to say adults reading aloud to children) avoiding the nightly reading. Harold is a loveable doofus while Chester is a more intelligent character and their interactions (Bunnicula never speaks) drive the story along. This really is a great book for the middle grades, never being too scary but having a slight element of suspense that should keep the most jaded 8-10 year old reading along.