With the arrival of warm weather and good fishing, life should be great for J.W. Jackson and his wife, Zee. Something's wrong, though. The morning newspaper brings an update on the case of the Headless Horseman, a corpse found six months ago. Such murders are rare on the Vineyard, and J.W. wonders if a killer is wandering free on the island. Something's wrong at home, too. Zee seems curiously distant. J.W. gets a distraction in the form of Abraham Mahsimba, a mysterious man searching for two ancient soapstone eagles. Mahsimba follows their trail to the Vineyard and enlists J.W.'s help. The search for the eagles pits them against some of the most powerful figures in the Vineyard's art world, including some who would stop at nothing to add forbidden objects to their collections.