The Secret of the Missing Grave — David A. Crossman / D.A. Crossman

Bean and Ab are expecting to spend a normal, fun summer together on the Main island where Bean lives. Things quickly become exciting however, when Ab tells Bean that the Moses Webster House, the boarding house where she is staying with her parents, is haunted.
What follows is a set of entertaining adventures as the two search for a buried treasure. But first they must find the secret tunnel connecting the Moses Webster House to the spooky Winthrop House, get past the sinister Maud Valliers, and dodge Bean's nasty Cousin, Monty.
A series of frightening and dangerous missteps leads them to a bizarre treasure - and even darker secrets. In the process they become heroes in their close-knit island community.