The Wall by Mary Roberts Rinehart

Trade paperback format.  Part of Otto Penzler's excellent American Mystery Classics series.  A murder at a seaside estate brings a wealthy family’s buried conflicts to the surface Marcia Lloyd and her brother Arthur have spent every summer of their lives exploring the grand halls and seaside grounds of their family’s idyllic vacation home, a gorgeous old mansion called Sunset House built by their grandfather. But when Arthur’s ex-wife Juliette arrives at Sunset to demand alimony from him, things take a dark turn and Juliette disappears―her body found a week later. What sordid secrets lie within the creaky old manor? Marcia and the local sheriff Russell Shand must work against the clock to find the murderer in this seemingly utopian upper-class hamlet. From “the American Agatha Christie” Mary Roberts Rinehart comes a Golden Age murder mystery inspired by her own hauntingly beautiful coastal northeastern home in Bar Harbor; The Wall is both a love letter to quiet waterfront towns as w