Death on a vineyard beach: a Martha's Vineyard mystery

For ex-cop J.W. Jackson, a Vineyard summer spent honeymooning with the fetching Zee Madieras is as good as life gets.
But when Zee and J.W. treat themselves to a matinee performance of the opera Carman in Boston, a hooded figure with a sawed-off shotgun cuts their idyll short. J.W., reacting just in time, foils the attempted murder of an aging former gangster, Luciano Marcus.
Marcus, who lives in a magnificent, secluded Vineyard estate at Gay Head, understandably wants to keep the situation quiet. Suspecting island links to the assault, he persuades a somewhat reluctant J.W. to look into the matter. J. W., who would much rather just enjoy some quiet times with Zee, quickly finds himself up to his fishing rod and cooking utensils in a complex and surprising mystery.
Marcus's commission leads J.W. into the local Wampanoag Indian community, where several people apparently have reason to wish Marcus dead and gone. J.W. meets the enigmatic Bill Vanderbeck, a Wampanoag thought by some to be a shaman, and he must also confront a man from his own distant past, the mysterious Joe Begay, who once saved J.W.'s life. Now, on the Vineyard, Joe is married to a member of a well-known Wampanoag family.
It's an intriguing case with many elements, but J.W. worries that it could also mean danger for Zee, who saw the face of one of the would-be assassins.