"Warren Duffy has returned to America for all the worst reasons: his marriage to a beautiful Welsh woman has come apart; his comic shop in Cardiff has failed; and his Irish-American father has died, bequeathing to Warren his last possession, a roofless, half-renovated mansion in the heart of black Philadelphia. On his first night in his new home, Warren spies two figures in the grass outside; when he screws up the nerve to confront them, they disappear....