Prince of Darkness [first edition]

Romance novel with Suspense and Mystery. From dust jacket flap: Middleburg, Maryland...a sleepy old Colonial town, where the wealthy weekenders of Washington and Baltimore mingled with descendants of the seventeenth-century founders, to enjoy a life of fox hunting, tradition, and harmless snobbery....Or was it so harmless? Peter Stewart, a mysterious visitor from England, saw the quiet town through different eyes --- as a sleeping cat, watching his own odd activities through slitted eyelids, wary, alert AND treacherous !