Old Metairie Mystery Book Club - Saltwater by Katy Hays

The world was shocked by playwright Sarah Lingate's death thirty years ago at a Moorish, whitewashed villa on the island of Capri. Absolved of the crime, the Lingate family maintains that what happened that night was a tragic accident, and every July they come back to prove it's true. This time, Helen Lingate, sole heir to the family fortune, has a plan.